Answer:
If a = b, then a - c = b - c
hope it helps
Answer:
20 parts
Step-by-step explanation:
7:5
28:x
7*4=28, 5*4=20; x=20
28:20
Area of sector=fraction of sector times area of circle
fraction of sector=degrees/360
and area of circle=pir^2
so
hold a sec, we have the wiper on the outside, so we want to find the outside ring thing
do
area big sector-area small sector
or even better
(degrees/360) times (area big-areasmall)
big is 10
small is 4 (10-6=4)
areabig=10^2 times pi or 100pi
areasmall=4^2 times pi or 16pi
areabig-areasmall=100pi-16pi=84pi
then find the fraction
84pi times (150/360)=35pi square inches
35+15x=410
410-35=375
375/15=25
He will need to work 25 weeks.
I believe A and B are the ones. As for explaining? hmm. I would honestly say that any number to the right of a number is a tenth of the place above it. But then again, it's optional to explain ;P