CPhill

Nice explanation, tertre...!!!

The scalle factor  of the larger triangle to the smaller  = 

sqrt  [ larger area / smaller area ] =    

sqrt  [ 150 / 6]  =

sqrt (25)   =  5

The legs of the smaller triangle are   3  and 4

The legs of the larger triangle are each  5 times as much =  15 and 20

So...the sum of the legs of the lager triangle   = 15 + 20   = 35 units

...."  What is the ratio of the area of △PQT to the area of △P  "

What  is the second triangle  ???

15x^2 - 8x - 7   factors as  (15x + 7) (x - 1)

x^2 - 2x + 1   factors as  ( x - 1) (x - 1)

So we have

[ (15x + 7) (x - 1) ] / [ ( x - 1) (x - 1)  ]      ...cancel the  x - 1  factors on top/bottom and we have

[15x + 7 ]  / [ x - 1 ]    =    tiles needed

Not totally sure about this, NSS...but here is my  best shot....

APY  = (1 + r/n)^n - 1

APY for monthly compounding =  (1 + .055/12)^12  - 1  ≈  .05640  ≈  5.640%

APY  for quarterly compoundng   = ( 1 + .055/4)^4  - 1  ≈  .05614 ≈ 5.614%

[5.640 - 5.614 ] ≈  .026%

Interest  = Pricipal *rate * time

1242 * .0125 * 1 month   =  $15.53 ⇒ B

 The ratio  area of triangle  PQT   to the area of  triangle  P (what)    ????

Using the answer from 9, we have

Total payback / 24 months

[2741.04] / 24   =  $114.21

We don't need to do any math here, NSS....we can't pay back less than $2500....so "D"  must be correct

NSS...I think the answer is 8000/18  =  $444.44 ⇒  "B"