Answer:
[tex]4\frac{1}{2}[/tex] cups plaster of paris.
Step-by-step explanation:
Given:
for one batch of sidewalk chalk = [tex]1\frac{1}{2}[/tex] cup plaster of paris.
Number of bathes = 3
We need to find quantity of plaster of paris.
Solution:
For making 1 batch of sidewalk chalk = [tex]1\frac{1}{2}[/tex] cup plaster of paris.
For making 3 batches of sidewalk chalk = [tex]3\times 1\frac{1}{2}[/tex] cup plaster of paris.
[tex]= 3\times \frac{2\times 1+1}{2}[/tex]
[tex]= 3\times \frac{2+1}{2}[/tex]
[tex]= 3\times \frac{3}{2}[/tex]
[tex]= \frac{3\times 3}{2}[/tex]
[tex]= \frac{9}{2}[/tex]
[tex]=4\frac{1}{2}[/tex]
Therefore, he needed [tex]4\frac{1}{2}[/tex] cups plaster of paris.
