Answer:
Is there a picture to go with it?
Step-by-step explanation:
3/4 = .75 so you have to find 75 % of 3/9
100% = 3/9
1% = (3/9)/100
75% = (3/9)/100 * 75 =.25
You can cross multiply to find the answer. Start by setting up your equation:
45/30 = 60/x (30 represents half an hour)
Next, cross multiply, 45 times x, and 60 times 30:
45x = 1800 you must isolate the "x" value by using the opposite operation it is involved in. Here we have 45x (x is multiplied to 45) so we must divide 45, which will cancel itself out, leaving us with "x."
What you do on one side of the equation, you must do on the other, so divide 1800 by 45 as well, which will leave you with 40.
Working it out on paper, your equation should now look like this: x=40, which represents the amount of time it will take to fill a 60 gallon tube.
Answer: It will take 40 minutes to fill a 60 gallon tube.
I'm thinking this is what the problem looks like:
. The first thing to do is to move the
over to the other side because it has a common denominator with the other side. Doing that and at the same time combining them over their common denominator looks like this:
. The best way to solve for x now is to cross-multiply to get 3(4-x)=-4(x-4). Distributing through the parenthesis is 12 - 3x = -4x + 16. Solving for x gives us x = 4. Of course when we sub a 4 back in for x we get real problems, don't we? Dividing by zero breaks every rule in math that there ever was! So, yes, the solution is extraneous.
If an ostrich can run 50 miles in one hour then he can run 12.5 miles in 15 minutes. 15 minutes is 1/4 of an hour. Multiply 50 by 0.25 = 15.