Question
βAβ alone can complete a work in 15 days while
βAβ and βBβ together can complete the same work in 10 days. How much percentage of the work, βBβ alone can complete in 21 days?Solution
Let the total work = L.C.M of 15 and 10 = 30 units Then, efficiency of βAβ alone = 30 Γ· 15 = 2 units/day Combined efficiency of βAβ and βBβ = 30 Γ· 10 = 3 units/day So, efficiency of βBβ = 3 β 2 = 1 units/day So, work done by βBβ alone in 21 days = 1 Γ 21 = 21 units So, percentage of work completed by βBβ = (21 Γ· 30) Γ 100 = 70%
10 years ago, the age of βPβ was 50% more than the age of βQβ. If the sum of their present ages is 75 years, find the present age of βPβ.
Pintu' is father of 'Qasim'. '2x' years ago from now, the age of 'Pintu' was four times the age of 'Qasim'. While, '2x' years hence from now, age of 'Pi...
Ratio of present age of a father to that of his son is 9:2. After 4 years the ratio will become 4:1. What is the difference (in years) in their present...
At the time of their marriage, the ages of Karan and Divya were in the ratio 13:12. Two years before their marriage, Karanβs age was 10% more than Div...
8 years ago from now, ratio of ages of βRβ and βLβ was 3:5, respectively. If βLβ is 7 years elder to βRβ, then what will be the age of οΏ½...
The present ages of a father and his son are in the ratio 7 : 3. If 5 years ago the father was three times as old as his son, what is the sum of their p...
A and B are two friends. 9 years hence, age of A will become 2.5 times the present age of B, and the age of B will become 30% less than the present age ...
10 years ago, the ratio of the ages of Maya and Neil was 4:3. The present age of Jake is 10 years more than one-fourth of Neilβs present age. Find the...
Present ages of P and Q are in the ratio 2:5 respectively. If Qβs age, 15 years hence from now will be 5 times of Pβs age, 5 years ago from now, the...
What is the value of 'x' such that, given their current ages are in a 3:7 ratio, 'x' years ago, the ratio of 'Adarsh' and 'Malik's ages was 1:3, and if ...
Relevant for Exams:
