SOLUTION: 8 students can solve 20 questions in 10 minutes. How many students will be needed to solve 30 problems in 5 minutes

Algebra ->  Rate-of-work-word-problems -> SOLUTION: 8 students can solve 20 questions in 10 minutes. How many students will be needed to solve 30 problems in 5 minutes      Log On


   

Question 1070545: 8 students can solve 20 questions in 10 minutes. How many students will be needed to solve 30 problems in 5 minutes
Found 2 solutions by DENNIS DON, ikleyn:
Answer by DENNIS DON(8) About Me  (Show Source):
You can put this solution on YOUR website!
students : questions: time
8. : 20. : 10
x. : 30. : 5

x=%288%2A30%2A10%29%2F%285%2A20%29
x=24

Answer by ikleyn(52748) About Me  (Show Source):
You can put this solution on YOUR website!
.
The rate of each student (assuming the rate is constant for all students) is 20%2F%288%2A10%29 = 20%2F80 = 1%2F4 of the problem per minute.


Therefore, the number of students under the question is

n = 30%2F%28%281%2F4%29%2A5%29 = %2830%2A4%29%2F5 = 6*4 = 24.


Answer. 24 students.

For many other similar solved problems see the lesson
    - Rate of work problems
in this site.

Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lesson is the part of this textbook under the topic "Rate of work and joint work problems" of the section "Word problems".