Bryan and Adam have 40 marbles.
Bryan has 20 less marbles than Adam.
Find the number of marbles that Adam has.
- Which model should we draw?
(1) Model Part-whole
(2) Model Comparison
- Is the total given?
(1) Yes
(2) No
- Who gets the shorter bar?
(1) Bryan
(2) Adam
- Number of marbles that Adam has =
(a)
Which model should we draw?
(1) Model Part-whole
(2) Model Comparison
We should draw a (2) Model Comparison.
(b)
Is the total given?
(1) Yes
(2) No
(1) The total is given.
(c)
Who gets the shorter bar?
(1) Bryan
(2) Adam
Bryan has 20 less marbles than Adam.
So, Bryan (1) gets the shorter bar.
(d)
If 20 more marbles are given to Bryan, Bryan and Adam will have the same number of marbles.
Number of marbles that Adam has
= (40 + 20) ÷ 2
= 60 ÷ 2
= 30
Answer(s): (a) 2; (b) 1; (c) 1; (d) 30