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5) Two Customers took out car loans from a bank.

Marcus took out a 5-year loan for $10,000 and paid 4.7% annual simple interest.
Gianna took out a 6-year loan for $10,000 and paid 4.5% annual simple interest.

What is the difference between the amounts of interest Marcus and Gianna paid for their car loans?

S.I of Marcus loan = P × R × T/100

= 10000 × 4.7 × 5/100

= $2350.

S.I of Gianna loan = P × R × T/100

= 10000 × 4.5 × 6/100

= $2700.

Difference in Interest = $2700 - $2350

= $350.

Hence, Gianna paid $350 more interest on her loan.

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204