Answer:
3003.
Step-by-step explanation:
This is the number of combinations of 5 books from 15 = 15C5
= 15! / 10! 5!
= 15*14*13*12*11 / 5*4*3*2*1
= 3*7*13*11
= 3003.
Answer:
c
Step-by-step explanation:
Work in the rates / minute
wilma:- in 120 minutes she mows 1 lawn
so in 1 minute she mows 1/120 lawn
similarly, Rock mows 1/80 lawn in 1 minute
working together 1/120 + 1/80 = 1/x where x is number of minutes working together
1/20 + 1/80 = 1/48
so 1/x = 1/48
x = 48
answer is 48 minutes
Rational means it has an end with its decimal points and a real number is a number with a decimal point:
An example of these two would be 1.5
Hope this helps! :)
