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1 vote
What is the missing number in the data set 15,17,28,30 if the mean is 23

User Framara
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2 Answers

3 votes
15+17+28+30=90, if theres another number than there r 5 total numbers, 23*5=115, 115-90=25, so 25
User Vakas
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7.9k points
4 votes
mean is add the numbers and divide the result by how many numbers there are
mean=23
1 missing number which is x
5 numbers including missing one
(15+17+28+30+x)/5=23
solve for x
multiply both sides by 5
15+17+28+30+x=115
add like terms
90+x=115
subtract 90
x=25

the missing number is 25
User Lah
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6.9k points