Question

There are 90 students in a speech contest. Yesterday 2/3 of them gave their speeches. Today,1/3 of the remaining gave their speeches. How many students still haven't given their speeches?

Answer 1

The number of the students is 20.

Explanation:

Total number of students in the speech contest = 90

Number of students that gave their speeches yesterday =
`(2)/(3)` of 90

=
`(2)/(3)` x 90

= 60

Number of remaining students who have not given their speeches after the first day = 90 - 60

= 30

Number of students that gave their speeches today =
`(1)/(3)` of 30

=
`(1)/(3)` x 30

= 10

Number of students that have not given their speeches = 30 - 10

= 20

Thus, 20 students have not given their speeches.