The farmer had 156 sheep to start. I can’t seem to post my model.
I started with two tapes and partitioned both in two parts. I added a third part to the sheep tape because I knew it had to be 3 times more than half the goat tape in the end.
So then I added the goats and the sheep plus 36 ( 320) then divided by five to get 64. Each of the 5 parts equaled 64 beasts. in the end, there were 192 sheep ( 64×3) I subtracted the newly purchased ovine creatures to find the original amount. 192-36 = 156 sheep.

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I just added the solution to the challenge. I hope my tape diagram makes sense!

The farmer had 156 sheep to start. I can’t seem to post my model.

I started with two tapes and partitioned both in two parts. I added a third part to the sheep tape because I knew it had to be 3 times more than half the goat tape in the end.

So then I added the goats and the sheep plus 36 ( 320) then divided by five to get 64. Each of the 5 parts equaled 64 beasts. in the end, there were 192 sheep ( 64×3) I subtracted the newly purchased ovine creatures to find the original amount. 192-36 = 156 sheep.

.

I just added the solution to the challenge. I hope my tape diagram makes sense!