Answer:
78
Step-by-step explanation:
You take the original total: 60, and multiply it by 30 to get 1,800. You then divide 1,800 by 100 to get 18. 18 is your 30%. Now, you add the 30% to 60 getting your total number of ducks: 78.
The equation version:
It is just proportions.
Answer:
18 Minutes
Step-by-step explanation:
Simon and sophie each do a fraction of the job per minute like this:
-Simon does per minute (if we multiply this by 30 we have the completed job)
-Sophie does of the job per minute (again if we multiply this by 45 we have the completed job)
We will add this two to know how much of the job they do together in a minute:
They will do of the job per minute.
So the total time will be when they do , we can put this in one equation like this:
where x is the total times we need to do of the job to complete it. We solve for x: