Area of right-angled triangle is given by;
Area, A = 1/2 *b*h, Where b=base, h=height
Therefore,
A1 = 1/2bh = 16 in^2
A2 = 1/2 (2b)(2h) = 2bh
Ratio of increase = A2/A1 = {2bh}/(1/2bh} = 4 (the area is increased 4 times)
The,
A2 = 4*16 = 64 in^2
Therefore,
The area is increased by (64-16) = 48 in^2
Brian-90×5+85=535
Christina-90×5+65=515
So after 5 weeks Brian will do 535 push ups and Christina will have done 515.
