Academy girl calculation

There are 180 pupils in the first year of the academy. Seven girls for every five boys, so there are how many girls in the year?

Final Answer:

d =  105

Step-by-step explanation:


d+c = 180
5d = 7c

d+c = 180
5·d = 7·c

c+d = 180
7c-5d = 0

Pivot: Row 1 ↔ Row 2
7c-5d = 0
c+d = 180

Row 2 - 1/7 · Row 1 → Row 2
7c-5d = 0
1.71d = 180


d = 180/1.71428571 = 105
c = 0+5d/7 = 0+5 · 105/7 = 75

c = 75
d = 105

Our linear equations calculator calculates it.



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algebrabasic operations and conceptsnumbersGrade of the word problem

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