Step by step
The question
Question: share 84 in the ratio 3 to 4 to 5.
The ratio says how many equal parts each one gets: 3 for the first, 4 for the second and 5 for the third.
Careful!
3 to 4 to 5 does not mean dividing 84 by 3 and by 4 and by 5.
It counts parts of the same size.
1 Count the parts
All together there are 3 plus 4 plus 5: 12 equal parts.
2 Draw the bar
3 Find one part
12 parts make 84.
So one part is 84 divided by 12: 7.
Every part is 7.
4 Find each share
The first share has 3 parts: 3 times 7 is 21.
The second share has 4 parts: 4 times 7 is 28.
The third share has 5 parts: 5 times 7 is 35.
So the shares are 21, 28 and 35.
5 Check
Let's check.
The shares add up: 21 plus 28 plus 35 is 84.
And divided by 7, they give 3 to 4 to 5 again.
So the answer is right!
Let's look back.
First: count the parts.
Then: draw the bar.
Then: find one part.
Then: find each share.
Last: check.