SOLUTION: Please help me with this problem: Two fifths of the sum of a number and 4, plus -7 is -16. Write an equation that can be used to determine the number and then determine the number.
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Question 967099: Please help me with this problem: Two fifths of the sum of a number and 4, plus -7 is -16. Write an equation that can be used to determine the number and then determine the number. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Two fifths of the sum of a number and 4, plus -7 is -16.
Just write an equation for exactly what it says (n + 4) + (-7) = 16
which is (n +4) - 7 = 16
Get rid of the fraction, multiply each by 5
2(n + 4) - 35 = 80
2n + 8 - 35 = 80
2n - 27 = 80
2n = 80 + 27
2n = 107
n = 107/2
n = 53.5
:
;
See if that works in the original equation, use .4 for 2/5
.4(53.5 +4) + (-7) = 16
.4(57.5) - 7 = 16
23 - 7 = 16
