To solve this problem, we can set up proportion, which is two equivalent ratios. In this case, we are using the ratio of A to B to figure out the amount that B pays using our value for A. We are allowing x to represent the unknown value for the B payment. This is modeled below:
3/2 = £125/x
To simplify, we can perform cross-multiplication. This means multiplying the numerator of one fraction by the denominator of the other and setting it equal to the product of the other numerator and denominator. This is modeled below:
(125)(2) = (3)(x)
Next, we can simplify the equation by performing the multiplication on both sides of the equation.
250 = 3x
Finally, we should divide both sides by 3 to get our unknown variable x alone on the right side of the equation.
x = 83.33
Therefore, B costs £83.33.
Hope this helps!