How to do simultaneous rates?
i thought you add just them and solve
20 minutes= 1/3 of an hour
30 minutes = 1/2 of an hour
1/2+1/3= 5/6 x?
d=r*t
1= 5/6t
but my answer is wrong!
Simultaneous rates? easy help
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Aside from Mike22629's formula to solve this problem, this problem can also be solved by doing the following:
Let the depth of the pool equal x.
The smaller hose can fill the pool at x/30 per min and the bigger hose can fill the pool at x/20 per min. From this, we can conclude that both hoses can fill the pool at x/30+x/20= x/12 per min simultaneously. Now, we need to know how many minutes it'll take the fill the pool, which is of depth x. Since both hoses fill the pool at x/12 per min, we can do (x)/(x/12) to find out how many mins it'll take them to fill the whole pool. The answer comes out to be 12.
Let the depth of the pool equal x.
The smaller hose can fill the pool at x/30 per min and the bigger hose can fill the pool at x/20 per min. From this, we can conclude that both hoses can fill the pool at x/30+x/20= x/12 per min simultaneously. Now, we need to know how many minutes it'll take the fill the pool, which is of depth x. Since both hoses fill the pool at x/12 per min, we can do (x)/(x/12) to find out how many mins it'll take them to fill the whole pool. The answer comes out to be 12.