Model Sum - P3

by Theresa
(Singapore)

My answer is 18 however the answer provided was 54. Please advise where I miss.


There are twice as many books in Box A than Box B. When some books are moved from Box A to Box B, the number
of books in Box B is 5 times as many as Box A. If there are 72 books in Box A at first, how many books are there left
in Book A in the end?

Zach's Answer:

Hi Theresa,

Your answer is correct, it should be 18. For the answer to be 54, the question should read "How many books are moved from Box A to Box B?" Let me know if you have further questions.

Comments for Model Sum - P3

Average Rating starstarstarstarstar

Click here to add your own comments

Feb 02, 2015
Rating
starstarstarstarstar 		First try
by: Alfie

A has 2 big blocks, B has 1 big block.
Divide the big blocks into 2.
A has 4 small blocks, B has 2 small blocks.
Move 3 small blocks from A to B.
So now B has 5 small blocks and A has 1 small block, fulfilling the requirements of the question. Now, 1 small block is 72/4 = 18
Aug 15, 2013
Rating
starstarstarstarstar 		Answer to the above question
by: Ms. Thaslim

Box A has twice as many books as box B. so,
B = 72/2 = 36
when some books are transferred to from box A to B, B has five times the books as in A. So we get 6 units totally. 1 for A and 5 for B (since B has 5 times the amount as in A).Therefore

A + B = 72+ 36 = 108
1 unit = 108 / 6 = 18
Thus Box A has 18 books at the end.

P.S sorry,I couldn't type-draw the block diagram in here.

Oct 01, 2012
Rating
starstarstarstarstar 		Please explain the solution
by: Kumar

Hi Zach,

Can you please explain the solution

Click here to add your own comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Ask Grade 3 Question or Post Answer/Comment.





Enjoy this page? Please pay it forward. Here's how...

Would you prefer to share this page with others by linking to it?

  1. Click on the HTML link code below.
  2. Copy and paste it, adding a note of your own, into your blog, a Web page, forums, a blog comment, your Facebook account, or anywhere that someone would find this page valuable.