Answer:
100 red bricks
Step-by-step explanation:
Let's say red bricks is equal to 5x
Gray bricks is equal to 2x
We have an equation
2x + 5x = 140
= 7x = 140
Divide through by 7 to get the value of x
X = 140/7
X = 20
Red bricks = 5(x)
= 5(20)
= 100
Gray bricks = 2(x)
= 2(20)
= 40
Therefore in conclusion the number of red bricks is 100.