This would be ELA 1 or 2.....
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
The shortcut is the hypotenuse of a right triangle with legs 6 and 8, so 6²+8²=c²
36+64=c
100=c²
c=10.
so he traveled 6+8+10=24km
The known facts
- the sum of Natalie's age and Fred's age is 36
- the sum of Fred's age times four and Natalie's age is 72
Now, let's set up the equations where N is Natalie's age and F is Fred's age.
N + F = 36 ---- equation 1
N + 4F = 72 ---- equation 2
equation 2 minus equation 1 ---> 3F = 36 ---> F = 12, thus N = 24
Thus Fred is 12 years old, and Natalie is 24 years old.
