Ratios

[adamnamsole]

So I need help on a easy question that I’m not getting. Attached in the picture is also the questions. Could I please get help with the process of how each question is answered.

 

[Dr.Peterson]

I'd take one robbery at a time. If 12 is divided in the ratio 1:3:2, how much does each one get? (Hint: how many "parts" are there in all? How much is each "part" worth?) Then put that information into a table.

Please show how you've tried to answer that one question; once we know you can do that, the rest shouldn't be hard.

Of course, you can answer part (a) before you do any of that; but you'll need to break down each robbery to answer (b) and (c).

 

[HallsofIvy]

Since Dr. Peterson posted that three years ago (I have no idea how I found it- I thought at first that it was posted last Monday), I will answer the question he asked.

If x, y, z are three numbers that divide 12 in the ratio 1:3:5 then x+ y+ z= 12 while y= 3x and z= 5x. So we get x+ 3x+ 5x= (1+ 3+ 5)x= 9x= 12. (The "9" is what Dr. Peterson mean by "how many "parts" are there in all?") So x= 12/9= 4/3. (Each "part" is worth 4/3. x= 4/3, y= 3(4/3)= 4, and z= 5(4/3)= 20/3. Of course x+ y+ z= 4/3+ 4+ 20/3= (4+ 12+ 20)/3= 36/3= 12.[edited]

(I wonder how many students had trouble with just because they assumed the answers must be integers.)

 

[Otis]

… Dr. Peterson posted that three years ago …

Halls, I think you'd looked at the date underneath Dr. Peterson's name. That's the date he joined the forum.