Answer:
There are 36 scholars who have a sister.
Step-by-step explanation:
Given that:
Total number of scholars in classes = 90
Fraction of scholars who have a sister = 2/5
Fraction of scholars who have a brother = 1/2
Number of scholars who have sisters = 2/5 of 90
Number of scholars who have sisters = [tex]\frac{2}{5}*90[/tex]
Number of scholars who have sisters = 36
Hence,
There are 36 scholars who have a sisters.