Can't read the top questions mate !
3/4 is 1/3 of what number?
For this problem we just need to do the following division:

And we can solve for the value of x desired and we got multiplying both sides by 3:

So then we can conclude that 3/4 is 1/3 of 9/4
Answer: 9/4
Expression:
Only three rectangles are needed, the one at the bottom and the two at the sides.
I hope this helps.
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