Question
'R' takes 20 days to complete a task, and 'A' takes 30
days to do the same task. To finish the job in just 6 days, what percentage increase in their respective efficiencies is required by 'R' and 'A'?Solution
We can say that Let the total work = 60 units (L.C.M of 20 & 30) Efficiency of 'R' = 60/20 = 3 units /day Efficiency of 'A' = 60/30 = 2 units/day Their combined efficiency = 2 + 3 = 5 units/day To complete the work in 6 days, there combined efficiency should be 60/6 = 10 units/day Required percentage increase = {(10 – 5) × 100}/5 = 100%
If the sum of the ages of a father and his son is 60 years and the difference of their ages is 30 years, what is the father's age?
Three years ago, the ratio between the ages of 'A' and 'B' was 4:5, and eight years from now, the ratio will be 6:7. If 'C' is 12 years older than 'A', ...
The age of person A (y+3) years ago and the age of person B (y+4) years from now are in the ratio 2:3.
It is also given th...
In 6 years, Divya's age will be 40% less than Malu's age at that time, and currently, Divya's age is 25% more than Soni's age. Additionally, the age of ...
The average age of 26 children and their teacher's age are 22 years. If the teacher's age is excluded, the average reduces by 1. What is the teacher's age?
Two years ago, the combined ages of Armaan and Bikash equaled Chetna's age at that time. Ten years ago, Armaan was twice as old as Bikash. If, in five y...
Three years ago, the ratio of ages of P, Q, and R was 4:3:5. Present age of S is 40 years, who is 5 years older than R. Find the age of P five years fro...
The ratio of the present ages of a son and his father 3:7 and that of his mother and father is 6:7. Four years ago, the ratio of the age of the son that...
The average age of a group of 70 students is 14 years. If three students whose ages are 22 years, 20years, ________ years are replaced with th...
When 15 years is subtracted from the present age of A and the obtained result is divided by 4, then the present age of his nephew is obtained. If the pr...
Relevant for Exams:
