The Question:
BLYs Method
HSAs Method
SMAs Method
Would have done it similarly but without introducing the variable B, so all in terms of R
R : 4R
R+7 : 3(R+7)
We know the Bs were unchanged so
4R = 3(R+7)
Giving us R=21
And then B is 3(21+7)=84
The Question:
BLYs Method
HSAs Method
SMAs Method
Would have done it similarly but without introducing the variable B, so all in terms of R
R : 4R
R+7 : 3(R+7)
We know the Bs were unchanged so
4R = 3(R+7)
Giving us R=21
And then B is 3(21+7)=84
MathsHKO 
I like SMA’s approach of focusing on the unchanged and leaving in terms of r; although I’d use x to represent number of beads (any colour) since I’m predicting that pupils will be confused with blue beads represented with r.
HSA’s approach is really neat and demonstrates some pretty smooth thinking. 💭 BLY
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