Mental Maths Competition Topics Included. (1) Q. No. 1 to 50 are based on basic. Calculation questions related to Addition,

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1 Topics Included. () Q. No. to 0 are based on basic. Calculation questions related to Addition, Subtraction, Multiplication and Division, doubling and halving. () Student should know multiplication tables from to 0. () Number pattern. Doubling & Halving. () Mixed operations (BODMAS), Decimal Fraction, Fractions, time () L.C.M & H.C.F., divisibility of,,,,, 8, 9, 0, () Integers (Add, Subtract, Multiply, Divide) Mixed sums (7) Find day and date in a given calender year. (8) Calculation of percentage, Average, Ratio, simple equation, discount, profit & Loss percentage. (9) Square and Square root from to 0, Cubing a number from to (0) Conversions: kg hecto grm, deca gram, gram, decigram, centigram, miligram km hecto metre, deca mt, metre, deci mt, centi mt, mili mt. kl hecto litre, deca lt, litre, deci lt, centi lt, mili lt. () Area and perimeter of square and rectangle. Angles of a triangle. Instructions for the Competition. Time : ½hr. Students can use HB Pencil for marking answers in OMR sheet.. Result of the Competition will be declared on 8 th November, 0.. The application of rechecking of marks should be made within 0 days of declaration of results along with rechecking fees ` 00 in cheque only.. Every participant scoring more than % will be given certificate of participation.. Winners [ Rank to Rank ] from each std will be felicitated with Trophies in a specially arranged Award Function. 7. Medals for consolation prize winners [Rank th to Rank 0th] will be sent by courier at their residence along with the certificate.

2 SECTION (Mental Maths Calculation). (8 ) + (8 8) (a) 80 (b) 80 (c) 70 (d) 0. (9 ) ( 9) (a) 700 (b) 900 (c) 80 (d) 70. ( 7) + ( 9) + (8 7) (a) 7 (b) (c) 80 (d) 9. ( ) + (8 ) ( ) (a) 79 (b) 89 (c) 9 (d) 9. (8 ) ( ) + ( 9) (a) (b) (c) (d). (% of ) + (0% of 98) (a) (b) 0 (c) 0 (d) 0 7. (0% of 8) (% of ) (a) 0 (b) 0 (c) 0 (d) 0 8. (0% of 7) + (% of 0) (0% of 0 ) (a) 7 (b) 8 (c) 8 (d) 9 9. (half of 80) + (one third of 0) (a) 0 (b) 80 (c) 70 (d) (one third of 0) (half of ) (a) 7 (b) 7 (c) 7 (d). square of + square (a) 08 (b) 79 (c) 9 (d) 9. square of 8 square (a) 000 (b) 000 (c) 000 (d) 000. square of 0 + square of 0 square of (a) 07 (b) 0 (c) 00 (d) 0

3 . square of 8 square root of (a) 99 (b) 99 (c) 99 (d) 99. Select the greatest number from the given operations. (a) 98 (b) 98 (c) 98 + (d). square of 9 + cube root of (a) 8 (b) 8 (c) 9 (d) 0. square root of + cube of 8 (a) (b) (c) (d). Select the smallest number from the given operations. (a) (b) (c) 08 (d). If is divided by, the remainder is (a) (b) (c) 9 (d) 0 7. cube of + square root (a) 0 (b) 0 (c) 0 (d) 80. If 98 is divided by, the remainder is (a) (b) (c) 8 (d) 8. Sum of all the divisor of (a) 0 (b) 78 (c) 70 (d) 0 9. Sum of all the divisor of 0 (a) (b) 8 (c) 7 (d) 9 0. Sum of all prime divisors of 0 (a) 8 (b) 8 (c) 8 (d) 8. If 098 is divided by, the remainder is (a) 0 (b) 0 (c) 0 (d). If is divided by, the remainder is (a) 0 (b) (c) (d) (a) 97 (b) 98 (c) 99 (d) 0

4 (a) 90 (b) 90 (c) 90 (d) (a).8 (b).98 (c).7 (d) (a). (b). (c). (d) 0.. (a) (b) (c) (d) 7. (..9) + (7..) (a).0 (b).0 (c).00 (d).0. H.C.F. of, 7, 9 is (a) (b) (c) (d) 8. Double of 0 (a) 00 (b) 070 (c) 090 (d) 00. L.C.M. of, and 7 is (a) 0 (b) 0 (c) 80 (d) (a) 0.9 (b) 0.99 (c) 0.09 (d) Half of 098 (a) 9 (b) 9 (c) (d) 0 0. The ratio of min to hour is (a) : (b) :0 (c) :0 (d) : (a). (b).9 (c) 0. (d) (a) 0 (c) (b) 0 9 (d) 0 0 0

5 SECTION (Mental Maths Concepts). 0 0 ( ) (a) 0 (b) 00 (c) 0 (d) (a) 9 (b) 9. 9 ( 0) (a) (b) (c) (d). + 9 (a) 7 (b) 7 (c) (d). (0 8) (a) (b) (c) 7 (d). () () + ( ) () (). (a) (b) (c) (d) 88 0 (a) (c) (b) (d) 7 (c) (d) (a) 0 (b) 0 (c) 00 (d) (a) 0 (b) 00 (c) 00 (d) (a). (b).7 (c).9 (d) (a) 0 (b) 90 (c) 0 (d) 70. :70 7: (a) 9 (b) 8 (c) 7 (d) 7. Find nineth term in the given series.,, 9,,,, (a) 9 (b) 9 (c) (d). If bags of Soyabeen seeds cost ` 0. Find the cost of 7 such bags. (a) 00 (b) 0 (c) 00 (d) 70

6 . The perimeter of triangle is cm, if one of its side is cm. If the other two side are equal find their lengths. (a) cm (b) 0 cm (c) 0 cm (d) 8 cm y 8. then y (a) 0.8 (b) 0. (c) 0.9 (d) The ratio of meter: 0 cm is (a) : (b) : (c) : (d) : 8. The ratio of ` :7 paise (a) 8: (b) :8 (c) : (d) : 9. t 7t, t (a) 0 (b) (c) (d) 0. Find the number whose % is. (a) 0 (b) 00 (c) 00 (d) 00

7 SECTION (Mental Maths Challenge). Raj purchased following items from the supermarket 0 kg atta at ` per kg; kg dal moong at `.0 per kg, kg dal Udad at `.0 per kg and kg sugar at `.0 per kg. How much did he pay to the cashier, if the cashier gave him ` 7 back? (a) ` (b) ` (c) ` 7 (d) ` 00. Find the smallest number which on being divided by 0, 0, 0 and 7 leaves 8 as remainder. (a) (b) (c) 00 (d) 8. Find the radius of a circle whose circumference is. cm. (a). cm (b). cm (c). cm (d). cm. A car travels 79. km in 9 hours. Find the distance covered in hours. (a).0 km (b).9 km (c) km (d) 0.8 km. If a library there were 000 books. Out of this 7 books were discarded what percentage was discarded? (a) 8.% (b) 0% (c).% (d) % 7

8 . Sunil bought an old motor cycle for `000 and spent ` 000 for its repairs. For how much shall be sale it to earn profit of 0%? (a) `00 (b) `8000 (c) `9800 (d) ` To make 7 dresses 8. m of cloth was used. To make 7 dresses how much of the cloth will be required? (a). m (b). m (c) 90 m (d) 9 m 8. [. + {(. +.) + (7.8.)}] (a). (b) 8. (c) 0. (d). 9. In a hostel the consumption of wheat by 80 students in 9 month is 00 kg. Find the wheat required for 8 student in the same period. (a) 00 kg (b) 00 kg (c) 700 kg (d) 900 kg 70. The ratio of income to expenditure of Mr. Kiran is 9 : 8. Find his saving if his income is ` (a) ` 00 (b) ` 000 (c) ` 00 (d) ` 000 8

9 7. Calculate the number of years, months and days between and (a) Y-M-D (b) Y-8M-7D (c) Y-M-D (d) Y-8M-7D 7. If x, y, z and a, find the value of xy xy z a (a) (b) 0 (c) (d) 0 7. Divide 0.00 by. (a) 0.0 (b) 0.00 (c) (d) The square plot has a side 80 m long. Find the cost of levelling if at `.0 per sq.metre. (a) ` 0.0 (b) `.0 (c) ` 00 (d) ` 0 7. Simplify : (a).77 (b).9 (c). (d). 9

10 (Extra practise question). Ram, Ravina, Suresh and Srushti are respectively yrs months, years 9 months, year 7 months and years months old. Find their average age. (a) yrs months (b) yrs months (c) yrs month (d) yrs months. The H.C.F and L.C.M. of two number are 9 and 80 respectively. If one of the number is, find the other one. (a) 0 (b) (c) 0 (d) 80. Andy borrows a sum of ` 00 from Richa at the rate of 8% p.a. After year 8 months, how much simple interest will he have to pay? (a) ` 88 (b) ` 80 (c) ` 8 (d) ` 8. There are 800 books in a library. If.% new books were purchased and 00 old books were discarded, how many books were left in the library? (a) 00 (b) 00 (c) 000 (d) 00. Simplify: (a) 709 (b) 799 (c) 709 (d) 709 0

11 . A student has to secure % of the maximum marks to pass. He secures 80 marks and fails by 7 marks. Find the maximum marks. (a) 00 (b) 800 (c) 00 (d) of of 8 (a) (b) (c) (d) 8. Manan repaid ` 00 in 8 months which he had borrowed at.% per annum. How much simple interest did he pay. (a) ` 7.0 (b) ` 7. (c) ` 9 (d) ` Find the difference of the greatest and least numbers of five digits by formed by using 0,,, and once only. (a) 0870 (b) 090 (c) 7 (d) What is the th term of the sequence shown? 80, 0, 0,... (a) (b) (c) (d)

12 . A square & a rectangular plot of land have same perimeter. If the square is of side 0 cm & rectangle is of length 70 cm, then the area of the rectangle is (a) 00 cm² (b) 800 cm² (c) 00 cm² (d) 00 cm². A boy is yrs younger than his father. Three years ago, the boy s age was one-sixth of the age of his father, then present age of boy is (a) 0 yrs (b) yrs (c) 8 yrs (d) yrs. In a two digit number, the unit place digit is. If the digits are interchanged, the new number formed is times the old 8 number. What is the number? (a) (b) (c) 7 (d). The speed of car is km per hour. What is the distance 7 travelled in hours & minutes? (a) km (b) km (c) km (d) km A reduction of 0% in the price of sugar enables Mrs. Lal to buy an extra kg of it for ` 0. What is the reduced price per kg? (a) `.80 per kg (b) `.0 per kg (c) ` per kg (d) `.90 per kg

13 . This year, your brother Pratham will be yrs from being twice as old as your sister Jeet. The sum of Pratham s age & three times Jeet s age is 8. How old is Jeet? (a) yrs (b) yrs (c) yrs (d) yrs 7. Which of the following expression is correct? (a) (b) (c) (d) A swimming pool is 0 m long & wide. How many Kilolitres of water must be pumped into it so as to raise the level of water by. m? (a).0 kl (b) 0. kl (c) 0. kl (d) 0 kl 9. If 9.% of the students are present in the school & number of absent students is, find the total number of students in the school. (a) 00 (b) 00 (c) 80 (d) 0 0. The cost of a wall clock is ` 0. Find the selling price if the gain is %. (a) ` (b) ` 0 (c) ` (d) `.0

14 . Simplify:- of 7 8 (a) (b) (c) (d). In an office 0 clerks get a salary of ` 00 each & officers get a salary of ` 00 each. Find the average salary of the employee in the office. (a) ` 00 (b) ` 000 (c) ` 00 (d) ` 900. If two complementary angles are in the ratio :. Find the smaller one. (a) 0 0 (b) 0 0 (c) 80 0 (d) The perimeter of a rectangular field is 0 m. If the length is 8 m, find its area. (a) 9 sqm (b) 79 sqm (c) 97 sqm (d) 9.7 sqm. There were only two candidates in an election. One got % votes elected by a margin of votes. The total number votes were (a) 00 (b) 00 (c) 700 (d) 800

15 Answer Sheet b d c b 7 a b c 8 b d c 9 c b a 0 b b d c a 7 c a 7 b 8 b d 8 a 9 b c 9 d 0 c b 0 b d a d d 7 b d a 8 c b b 9 b c b 0 c c b d c 7 c d 7 a 8 b b 8 b 9 c a 9 c 0 d a 7 0 b d a 7 d c 7 a 7 d d 8 b 7 d c 9 b 7 c a 0 b 7 b Answers for extra practice questions c 9 d 7 a b 0 d 8 d b a 9 b c c 0 c c c b d c b 7 c a a 8 c b c b

16 Section (Solution) ) Atta 0 0 Moong dal. Udad dal.. Sugar.. Total 7 He paid to cashier ` 00 ) L.C.M. of 0, 0, 0 and 7 is 00. Hence required number ) Circumference r 70) Income : expenses 9 : 8 Income : savings 9 : Income savings x x ) From till is years. Then till 7 00 is 8 months Then till 00 is 7 days.. r 7. 7 r r. cm distance ) Speed time km/hr distance covered in hrs.. km ) % of books discarded 7) xy z xy a () () 0 0 () () % 7) ) Total cost cost price selling price x x ) Cloth required for dress m Amt of cloth required 7.m.m. 7) Area of square (80)² 00 m² cost of levelling ) ) [. + {(. +.) + (7.8.)}] [. + { +.}] [. + { +.}] [. + 7.] [8.7] 8. 9) Students Months Wheat x Since No. of months is same, x

17 Extra Practice Questions (Solution) ) Average age Total age ( 7 9) months years. months ) L.C.M H.C.F Product of two numbers 9 80 x x 9 80 x ) P 00, R 8%, T yr 8 months yrs. of of of SI P T R 00 8) P ) No. of books 800 New books discarded old books 00 No. of books left ) , 7, 89, 87, 9 7, 0, 9 ) Passing marks max. marks passing marks 00 x x ) of of of 8 7 of 8 7 T 8 months R.% p.a. SI P T R yr. 9) Greatest number, 0 least number 0, difference, 97 0) ) Perimeter of square Perimeter of rectangle (0) (70 + x) x x 00 x 0 Area of rectangle cm² ) Present age of boy x Present age of father x + yrs ago, age of boy x age of father x + x + 7

18 x (x + ) (x ) x + x 8 x + x x + 8 x 0 x 8 ) Let the ten s digit x Number 0x + Number obtained by interchanging the digits 0 + x 0 + x (0x + ) x 0x + 0 0x 8x x x 7 The required number 7 ) 7 hrs and minutes 7 hrs hrs. 9 hrs. distance speed time km 8 ) Let the original price ` x per kg 0 New price x + x 00 x x Original quantity x 0 x 00 0 x x 80 x 80 x x Original price ` 0 reduced price per kg ) Present age of Jeet x yrs. Pratham s age x x + x 8 x 70 x 7) Option (a) is correct ) Volume 0. 0 m³ ( )cm³ l 000 (0 000)l kl kl 9) Present students 9.% Absent students %. 00 x 0) C. P S.P 00 0 x 0 x 00 x 00. x 00 New quantity 0 x / 0 x 00 x 7 ) of of 8 8

19 7 of 8 7 of 8 ) Total salary Average salary 000 ) Smaller angle 90 ) P (l + b) 0 (8 + b) b b Area l b 8 97 m² ) Winner % Looser 00 8% Margin 8 % x 00 x 00 x 00. 9