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Anna11 [10]
3 years ago
13

Jerry started doing sit-ups every day. The first day he did 15 sit-ups. Every day after that he did 2 more sit-ups than he had d

one the previous day. Today Jerry did 28 sit-ups. Write an equation that could be solved to find the number of days Jerry has been doing sit-ups since the first day.
Mathematics
2 answers:
zlopas [31]3 years ago
7 0
Y = sit ups, x= days

y= 2x + 15
33 = 2x + 15 (subtract 15 from both sides)
18 = 2x (divide both sides by 2)
9 = x, 9 days
lbvjy [14]3 years ago
6 0
Y=2x+15
where y=number of sit ups
x=number of days
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The 95% confidence interval for the mean is (5.73, 6.95).

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