Hi there
I am re-learning some math (on my own, no teacher or tutor), and having trouble understanding how they got the correct answers to this question. I've been looking all around the internet for similar problems with explanation, but not finding it. This is a question given on Khan Academy.
The question is: Rob spent 25% more time on his research project than he had planned. He spent an extra h hours on the project. Which two below represent the hours actually spent on it?
a) 4h
b) (1 + 25/100)h
c) 1.25h
d) 5h
e) (h/0.25)1.25
It gives the correct answers as choice d and e.
So h is the extra hours spent on the project.
In the explanation given, it sets it up as planned to spend h/25% hours, and actually spent is h/25% + h hours. I do not understand why h is divided by 25%. Wouldn't it be 25% of the hours planned plus the extra h hours to get total hours spent on the project? That would be set up as .25(hours planned) + h. This obviously is not correct though. I feel stupid for not getting this but it is really stumping me. Anyone able to give clarification?
I am re-learning some math (on my own, no teacher or tutor), and having trouble understanding how they got the correct answers to this question. I've been looking all around the internet for similar problems with explanation, but not finding it. This is a question given on Khan Academy.
The question is: Rob spent 25% more time on his research project than he had planned. He spent an extra h hours on the project. Which two below represent the hours actually spent on it?
a) 4h
b) (1 + 25/100)h
c) 1.25h
d) 5h
e) (h/0.25)1.25
It gives the correct answers as choice d and e.
So h is the extra hours spent on the project.
In the explanation given, it sets it up as planned to spend h/25% hours, and actually spent is h/25% + h hours. I do not understand why h is divided by 25%. Wouldn't it be 25% of the hours planned plus the extra h hours to get total hours spent on the project? That would be set up as .25(hours planned) + h. This obviously is not correct though. I feel stupid for not getting this but it is really stumping me. Anyone able to give clarification?