the mean of 5 numbers is 27. four of the numbers are24, 33, 27, and 31.What is the fifth number?
2007-12-15 09:19:03 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
(24 + 33 + 27 + 31 + x) / 5 = 27
115 + x = 135
x = 20
Fifth number is 20
2007-12-19 23:55:50 · answer #1 · answered by Como 7 · 3⤊ 0⤋
You can solve this by solving the following equation, based on the definition of mean:
(24 + 33 + 27 + 31 + n) / 5 = 27,
where n is the unknown number.
(If I punched everything in right on my calculator, I get n=20.)
2007-12-15 17:21:42 · answer #2 · answered by nicholasm40 3 · 1⤊ 0⤋
(24 + 33+ 27+ 31 + x ) / 5 = 27
115 + x = 27(5) = 135
x = 135 -115 = 20
2007-12-15 17:24:44 · answer #3 · answered by CPUcate 6 · 0⤊ 1⤋
the total = 27 x 5 = 135, so the fifth number is:
135 - the sum of the other 4
= 135 - 115
= 20.
2007-12-15 17:23:57 · answer #4 · answered by Twiggy 7 · 1⤊ 1⤋
(24+33+27+31+x)/5 = 27
(115+x)/5=27
23+(x/5)=27
x/5=4
x=20
20 is the 5th number
2007-12-15 17:23:17 · answer #5 · answered by b1gmuff 3 · 1⤊ 0⤋
20
2007-12-15 17:32:44 · answer #6 · answered by J 6 · 0⤊ 1⤋
The mean is the average. To average a set of numbers, add them all up, then divide by how many numbers you have. In this case you have five numbers. The fifth number is unknown, so let it equal x.
Write an equation where you add up all five numbers (including the x) and divide this sum by 5. The answer is the average, or the mean.
2007-12-15 17:24:11 · answer #7 · answered by Petri 3 · 1⤊ 1⤋