24-09-2021 Answers
1. Find the value to replace question mark if 121^3 * 11 / (1331^2) = 11?
Answer: 1
Solution: 1331 = 121*11
So the expression becomes,
11^6 * 11/(11^6) = 11. Hence ?=1
2. Find the value of (5555+3600)/1831
Answer: 5
Solution: 5555 = 5*1111, 3600 = 5*720
As 1831 = 1111+720, the expression can be written as 5*(1111+720)/(1111+720) = 5
3. Find the value of 12.05 * 6.3/0.7
Answer: 108.45
Solution: 12.05 * 6.3/0.7 = 12.05 * 63/7
= 12.05 * 9 = 12.05 * (10-1) = 120.5 - 12.05 = 108.45
4. Find the value of (2 - 1/3) (1 - 1/4)(1 - 1/5) ....... (1 - 1/99)(1 - 1/100)
Answer: 0.05
Solution: (2 - 1/3) = 5/3
(1 - 1/4) = 3/4
(1 - 1/5) = 4/5
(1 - 1/100) = 99/100
So expression becomes 5/3 * 3/4 * 4/5 * ..... 98/99 * 99/100 = 5/100 = .05
5. If a/b = 1/3 and 9a + b = 48, then find the value of a.
Answer: 4
Solution: a/b = 1/3, So b=3a.
using the other equation, 9a+3a = 48, a=48/12=4
6.
Answer: 9/11
Solution: Dividing by B, the expression becomes
(A/B - 1)/(A/B + 1) = (10-1)/(10+1) = 9/11
7. What is the value of 512/5 + 211/5 + 461/5 + 157/5 ?
Answer: 268.2
Solution: Dividing by 5 is nothing but multiplying by 2/10.
Hence the above expression becomes (512+211+461+157)*2/10 = (1341)*2/10 = 268.2
8. What is the value of the below expression?
Answer: 5997
Solution: The expression becomes 999*6 + (1/7 + 2/7 + ... + 6/7)
= 5994 + 21/7 = 5997
9. Find the value to replace question mark so that (7/15 + 2/5) * ? = 1/20
Answer: 3/52
Solution: As 15 is the LCM of denominators, 7/15 + 2/5 = 13/15
So 13/15 * ? = 1/20
? = 15/(13*20) = 3/52
10. Find the value of 3219/25 + 1121378/25 + 99129/25
Answer: 48949.04
Solution: 25 is nothing but 100/4
Hence the expression is (3219+1121378+99129)*4/100 = 4894904/100 = 48949.04
11. Find the value of (0.76 × 0.76 × 0.76 - 0.008)/(0.76 × 0.76 + 0.76 × 0.2 + 0.04)
Answer: 0.56
Solution: Here a=0.76 and b=0.2
The expression can be written as (a^3 - b^3)/(a^2 +ab + b^2) = a-b = 0.76-0.2 = 0.56
12. If a-b = 3 and a^2 + b^2 = 29, find the value of ab.
Answer: 10
Solution: (a-b)^2 = a^2 + b^2 -2ab
9 = 29 - 2ab, ab = (29-9)/2 = 10
13. Find the value of the expression below.
Answer: 200 and 172/315
Solution: To simplify, first consider the whole number part alone.
44 + 66 + 88 = 198
Now consider the fractions.
4/5 + 6/7 + 8/9 = (252+270+280)/315 = 802/315
So answer is 198 + 802/315 = 200 + 172/315 = 200 and 172/315
14. If a+b=5 and 3a+2b=20, then 3a+b is
Answer: 25
Solution: a+b=5, So 2a+2b=10.
As 3a+2b=20, a=10 and b=-5. So 3a+b = 30-5 = 25
15.
Answer: 4/3
Solution: Dividing by B, the expression becomes
(A/B + 1)/(A/B - 1) = (7+1)/(7-1) = 8/6 = 4/3
16. What is the value of the below expression?
143/11 + 1023/33 + 165/11
Answer: 59
Solution: Using the formula a^2 - b^2 = (a+b)(a-b), the expression can be written as
(12+1)(12-1)/(12-1) + (32+1)(32-1)/(32+1) + (13+2)(13-2)/(13-2)
= 13 + 31 + 15 = 59
17. Find the value of 9983 * 984 + 9983 * 6
Answer: 9883170
Solution: Given expression can be written as 9983 * (1000 - 16) + 9983 * 6
= 9983000 - 9983*16 + 9983 * 6 = 9983000 - 99830 = 9883170
18. If 1/3 + 1/2 + 1/x = 4, then what is the value of x?
Answer: 6/19
Solution: 1/x = 4 - (1/3 + 1/2)
= 4 - 5/6 = 19/6, So x = 6/19
19. Find the value of the below expression.
Answer: 1739832
Solution: 9999 1/29 = (10000 - 28/29) = (290000-28)/29 =
so expression becomes (289972/29) * 174 = 289972 * 6 = 1739832
20. What is the value when 8/13 is divided by 192/559 ?
Answer: 43/24
Solution: 8/13/192/559 = (8/13) * (559/192) = 43/24
Comments
Post a Comment