Answer: 6.1% decrease
Note: It appears that your teacher doesn't want you to type in the percent sign, as that's already covered for you.
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Step-by-step explanation:
The salary decreased by 51500-48355 = 3145
Divide this over the initial salary to get 3145/51500 = 0.0611 which is approximate.
This converts to the percentage 6.11% and that rounds to 6.1%
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As an alternative, you can use the formula method below
A = old value = 51500
B = new value = 48355
C = percent change when going from A to B
C = [ (B-A)/A ] * 100%
C = [ (48355-51500)/51500 ] * 100%
C = (-3145/51500)*100%
C = -0.0611*100%
C = -6.11%
C = -6.1%
The negative C value indicates a percent decrease.