When you arrive at the music store to buy the CDs and cassettes for the 10 people mentioned in example 6, you find that the store is having a sale. CDs now cost $11 each and cassettes now cost $7 each. Write an expression for the new total amount you will spend. Then evaluate the expression when 6 of the people get CDs.

For 10 people:

Cost CD'S: 10 x 11 = 110

Cost Cassettes: 10 x 7 = 70

Total Cost = 110 + 70 = 180

For 6 people:

Cost CD's: 6 x 11 = 66

Cost Cassettes: 6 x 7 = 42

Total Cost = 66 + 42 = 108

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.

5/20 so 25%

step-by-step explanation: