Can anyone help to solve this problem, using model rather than algebra. Thanks in advance.
The ratio of the number of pens in the Blue box and the Red box is 5:7. After 117 pens are removed from each box, the ratio of the number pens in the Blue and the Red Box becomes 1:4. What is the number of pens in the Red box at first?
B:5u
R:7u
B:1
R:4
7u:117
U calculate urself after so much clues
Btw i am in P5 too :)
Thx SB for helping. But 7u:117 does not look right. It does not give whole number.
Originally posted by SBS8033D:B:5u
R:7u
B:1
R:47u:117
U calculate urself after so much clues
Btw i am in P5 too :)
Your answer is wrong. the units in the first part of the question and the units in the 2nd part of the question are not the same size so you cannot combine them in this way.
The unit in the first part is 27 pens each and in the 2nd is 18 each (from algebra) so total red pens initially is 27X7=189
I suck at using models for maths so i'll leave to someone else to teach using the model method.