Solve the proportions, 4 : 5::8 :b
4/5 = 8/b
Cross multiply and solve for b.
To solve the proportion 4 : 5 :: 8 : b, we can use cross multiplication.
First, we write down the two ratios:
4/5 = 8/b
Now, we cross multiply by multiplying the numerator of the first ratio by the denominator of the second ratio, and vice versa:
4 * b = 8 * 5
Simplifying the equation, we have:
4b = 40
To solve for b, we divide both sides of the equation by 4:
b = 40/4
Simplifying further, we find that:
b = 10
Therefore, the value of b that satisfies the proportion 4 : 5 :: 8 : b is 10.