Answer with positive exponent =
or 
Answer with negative exponent = 
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Explanation:
The rule we use is

If we multiply two exponential expressions with the same base, then we add the exponents.
The base for each is 5. The exponents 4 and -7 add to -3.
This means

To convert to a positive exponent, we apply the reciprocal to the base. We go from 5, aka 5/1, to 1/5.
So, 
Marco needs to save a minimum of $420 more to buy a smartphone.
<u>Explanation:</u>
Cost of a smartphone = $495
Savings = $75
Least amount of money, m that needs to be saved = ?
Additional savings, m = Total - initial savings
m = $495 - $75
m = $420
The inequality equation would be 75 + m ≥ 495
Therefore, Marco needs to save a minimum of $420 more to buy a smartphone.
Answer:
<h2>
67.7</h2><h2 />
Step-by-step explanation:
perimeter = semicircle (x2) + parallelogram side (x2)
= 1/2 π 12 (x2) + 15 (x2)
= 37.7 + 30
= 67.7
Answer: 5/4
Step-by-step explanation:
I reciprocal of a number can be found if you flip the upper and bottom numbers. Example: the reciprocal of 8 is 1/8