Alan solved the proportion StartFraction x over 200 EndFraction = StartFraction 8 over 25 EndFraction as shown. StartFraction x over 200 EndFraction = StartFraction 8 over 25 EndFraction. (8) (x) = (25) (200). 8 x = 5,000. StartFraction 8 x over 8 EndFraction = StartFraction 5,000 over 8 EndFraction. X = 625. What is Alan's error?

He should have cross-multiplied 8×200 to get 1600, then divide 1600÷25=64

Step-by-step explanation:

Use logic. If the numerator of the given fraction is less than half of the denominator, the value of x will have to be less than half of 200.

It is also possible to see that the denominator 25 is a factor of 200. If you know that 25×8=200, you can multiply the numerator 8×8 to get 64.

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°