Answer:
143 oil changes
Step-by-step explanation:
Let's find out Frances' rate per 1 day. We can set up a proportion, since we know he can do 91 oil changes in 7 days:
, where x is the number of oil changes Frances can do in 1 day
Cross-multiply:
91 * 1 = 7 * x
7x = 91
x = 91/7 = 13
So Frances can do 13 oil changes in 1 day. Set up another proportion to find how many oil changes he can complete in 11 days:
, where y is the number of oil changes Frances can do in 11 days
13 * 11 = 1 * y
y = 143
The answer is 143 oil changes.
Hope this helps!
143
lets make a fraction:
so
91 oil changes/7days
lets take "x" as the unknown # of oil changes:
x/11
91/7=x/11
we can cross multiply:
91*11=7*x
1001=7x
143=x
so 143 oil changes in 11 days
c
2^8 2x2x2x2x2x2x2x2=256