Maths question about capacity?
2016-05-08 6:40 am
A completely filled car radiator with capacity 8 L contains a mixture of 40 percent antifreeze (by volume). If the radiator is partly drained and refilled with pure antifreeze, how many litres should be drained from the radiator so as to have a mixture of 70 percent antifreeze?
回答 (1)
2016-05-08 2:28 pm
✔ 最佳答案
Suppose x litres should be drained[ ( 8 - x )*40% + x*100% ] / 8 = 70%
( 8 - x )*0.4 + x = 8*0.7
3.2 - 0.4x + x = 5.6
0.6x = 2.4
x = 4
Ans: 4 L
收錄日期: 2021-05-02 14:08:19
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