The pattern is the amount you need to add increases by 2 each time. Ex. 1+1=2 2+3=5 3+5=8
So k=katie's' age
m=mara's age
k is 2 times as old as m
k=2m
sum is 24
add means sum
k+m=24
so we have
k+m=24 and
k=2m
subsitute
2m+m=24
add
3m=24
divide both sides by 3
m=8
subsitute again
k=2m
k=2(8)
k=16
katie=16
mara=8
Answer: 55
Explanation:
Find the area of the entire shape: 7x9=63
Find the area of the missing piece: 8
7-3=4 9-5=4 4x4=16 16/2=8
Find the area: 63-8=55