Answer:
27
Step-by-step explanation:
A perfect cube is a number that can be cubed into an integer. The only number here is 27, which is 
30 divided by 100 = 0.3 x 7.5 = 2.25 or 25%
Answer:
Julia found 5 coins
Step-by-step explanation:
lets take the # of coins julia found as "x"
alice found6
davi found 5
lucas found 6
and carter found 8
remember how to calculate mean( add all numbers and divide by the# of numbers)
so
6+5+6+8+x/5=6 (since there are "5" terms)
so
25+x/5=6
treat this like a linear equation so multiply by 5 on both sides
25+x/5(5)=6(5)
25+x=30
subtract "25 on both sides"
25-25+x=30-25
x=5
hope this helps