Question
A and B can together complete a task in 18 hours. After
6 hours A leaves. B takes 36 hours to finish rest of the task. How many hours would A have taken to do the task if he worked alone?Solution
Let the total number of units of work =108 A and B can do in 18 hours so 108/18 =6 units each hour they both can do 6 units For 6 hours they both worked and so 36 units is done so 108-36=72 units of work is done by B alone in 36 hours I.e 72/36 = 2 units per day Therefore a+b=6 a=6-2 a=4 units per day If A worked alone then 108/4 =27 hours
15.99% of 549.99 ÷ 11.17 = ? ÷ 20.15
74.91% of 639.95 – 599.98% of 45 + 119.987 = ?
(4.88 × 5.76)2 - ?2 = 39.89 × 19.86
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
(1800.23 ÷ 29.98) + (816.32 ÷ 23.9) + 1634.11 = ?
1449.98 ÷ 50.48 × 10.12 = ? × 2.16
36.05 × 5.02 + 12.052 = ? + 9.09 × 4.04Â
(31.9)3 + (34.021)² - (16.11)3 - (42.98)² = ?