Question
Person A is twice as efficient as Person B. Person B can
complete a certain task in 32 days, while Person C takes 4 days more than Person A to finish the same task. Which of the following could be the number of days they work together such that the task remains incomplete?Solution
According to the question,
Time taken by ‘A’ to complete the work = 32/2 = 16 days
Time taken by ‘C’ to complete the work = 16 + 4 = 20 days
Let the total work = 160 units
Efficiency of ‘A’ = 160/16 = 10 units/day
Efficiency of ‘B’ = 160/32 = 5 units/day
Efficiency of ‘C’ = 160/20 = 8 units/day
When they work together for 7 days, work done = (10 + 5 + 8) × 7 = 161 units
Therefore, maximum number of days they can work together such that the work doesn’t get completed is 6 days.
The average age of 21 children is 30 years. 4 new children, whose average age is 15 years, join them. Find the average age of the 25 children.
The average of the first 7 non-zero multiples of 18 is:
In an examination, the average marks obtained by the students is 40. After correcting the quantitative mistakes, the average of 50 students is reduced t...
Consider a group consisting of 16 females with an average age of 25 years and 20 males with an average age of 35 years. What is the approximate average ...
Average weight of 13 nurses is 45 kg. If the weight of one more nurse is included, then average weight is increased by 1 kg. Find the weight of the newl...
There are three distinct numbers ‘a’, ‘b’ and ‘c’. If, a = 150, (a + b) = 450 and (c – b) = 60, then find the average of a, b and c.
...The average of the present age of 'D' and 'E' is 40 years. If the ratio of the age of 'D' 5 years ago to the age of 'E' 5 years hence is 2:3, then find ...
The average age of 24 children and their teacher's age are 21 years. If the teacher's age is excluded, the average reduces by 1. What is the teacher's age?
The average age of three children in a family is 35% of the average of the age of father and the eldest child. The total age of the mother and the young...
The average age of 12 girls is 35 years. If the age of two more girl is added the average decreases by one and a half year. What is the sum of the age o...
Relevant for Exams:
