5/100 * 4 = 20/100 reduces to 1/5
S = n(a1 + an)/2
2S = n(a1 + an)
2S = na1 + nan
nan = 2S - na1
an = (2S - n a1)/n
X - <span>the cost of cell phone service before tax is added
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Answer:
12 hours per week
Step-by-step explanation:
1. Find how many hours she worked to make $3,000 (36x10=360 hours)
2. divide 360 hours by 30 weeks
she would need to work 12 hours per week to make $3,000
hope it will help u..........