Answer:
a. 12
b. 60%
Explanation:
40% of 30 Use a decimal equivalent for 40% to multiply by 30.
.40 × 30
= 12
12 members of the club are seniors. (If the number was 50%, that would be half, so 15 people. So 12 people for the 40% seems reasonable! You don't want to accidentally calculate 120 or 1.2, checking for reasonableness is a good strategy.)
Assuming that the club is made up of all students and no animals or members of the community or intergalactic aliens. If 40% are seniors, then the rest are not seniors, that would be 60%. 60% of the club members are not seniors.