A, B, and C have 2150 yen collectively. A has 120 yen more than B does. After C gives B 2/5ths of his money, B now has 220 yen more than A. How much money did A originally have?
Please include how to do it, step by step
Please include how to do it, step by step
A= B + 120
A - B = 120
B + 2/5 C = A + 220
5B + 2C = 5A + 1100
5A - 5B - 2C = -1100
A + B + C. = 2150 |×2|
5A - 5B - 2C = -1100 |×1|
2A + 2B + 2C = 4300
5A - 5B - 2C = -1100
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7A - 3B = 3200
7A - 3B = 3200 |×1|
A - B = 120 |×3|
7A - 3B = 3200
3A - 3B = 360
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4A = 2.840
A = 2.840 : 4
A = 710
A - B = 120
710 - B = 120
B = 710 + 120
B = 590
A + B + C = 2150
710 + 590 + C = 2150
C = 2150 - 710 - 590
C = 850
Thus, A have 710 yen.