Five Consecutive Integers

When 5 consecutive integers are added together and the sum is then multiplied by 5, the result is 225.  Which of
the following is the fourth of the 5 consecutive integers?
A.)  5
B.)  7
C.)  10
D.)  11
E.)  13
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x = first consecutive integer
x + 1 = second consecutive integer
x + 2 = third consecutive integer
x + 3 = fourth consecutive integer
x + 4 = fifth consecutive integer

5(x + x + 1 + x + 2 + x + 3 + x + 4) = 225   {the sum of the five consecutive integers is multiplied by 5}
5(5x + 10) = 225   {combined like terms}
25x + 50 = 225   {used distributive property}
25x = 175   {subtracted 50 from each side}
x = 7   {divided each side by 25}
​x + 3 = 10   {substituted 7, in for x, into x + 3, the fourth consecutive integer}

10 is the fourth consecutive integer

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