To find the range of checks for which a checking account at Long's Bank will generate more earnings income than one at Fellow's Bank, we need to compare the earnings equations for both banks.
Let I₁ represent the earnings at Long's Bank and I₂ represent the earnings at Fellow's Bank.
So we have:
I₁ = -0.06x + 8.3
I₂ = -0.02x + 6.6
To find the range of checks for which Long's Bank will generate more earnings income, we need to find the values of x for which I₁ > I₂.
Setting the two equations equal to each other and solving for x:
-0.06x + 8.3 = -0.02x + 6.6
0.04x = 1.7
x = 1.7 / 0.04
x = 42.5
So Long's Bank will generate more earnings income for a range of checks greater than 42.5 checks. Since you cannot have a fraction of a check, we can say that Long's Bank will generate more earnings income for 43 or more checks.
Checking account earnings at
Long's Bank are expressed by
the equation,I = −0. 06x + 8. 3
.
The earnings at Fellow's Bank
are modeled by
.I = −0. 02x + 6. 6
In both cases, x is the number of
checks written.
For what range of checks will a
checking account at Long's Bank
generate more earnings income
than one at Fellow's Bank?
Show your work or explain how
you got your answer.
1 answer