Answer :
You have not provided the ratio of red bricks to gray bricks.
Therefore, I'll just explain how to solve this problem in general with an assumption and you can apply this same method to the specific problem you have.
Assume:
The number of red bricks was 5 and the number of grey bricks were 2.
Step-by-step explanation:
This mean for every 5 red bricks we use 2 grey bricks
Thus for every [tex]2+5=7[/tex] bricks there are 5 red and 2 grey bricks
This gives us: [tex]\frac{5}{7}[/tex] red and [tex]\frac{2}{7}[/tex] grey bricks
Therefore, with 175 bricks used in all, we have:
175 × [tex]\frac{5}{7}[/tex] = [tex]\frac{875}{7}[/tex] = 125 red bricks and
175 × [tex]\frac{2}{7}[/tex] = [tex]\frac{350}{7}[/tex] = 50 grey bricks
Answer (with given assumption):
125 red bricks were used