Part 1: A year ago, Ray's puppy weighed 8 pounds. Now his puppy weighs 25 pounds
more. How much does Ray's puppy weigh now? Explain using pictures,
numbers, or words.

Puppy's current weight = 33 pounds.

Step-by-step explanation:

The weight of Ray's puppy 1 year ago = 8 pounds

All we need is to add the 8 pounds to 25 to determine the current weight.

i.e.

current weight = 8 + 25

                         = 33 pounds

Therefore, puppy's current weight = 33 pounds.

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.