Quinn is twice as old as karl and four years older than parker. the sum their ages is 21. how old is parker

Parker is 6 years old

Let q, p, k represent the ages of Quinn, Parker, and Karl, respectively.

... q = 2k . . . . . . Quinn is twice as old as Karl

... q = p+4 . . . . . Quinn is 4 years older than parker

... q + p + k = 21 . . . . the sum of their ages is 21

We can use the first two equations to find Karl's age in terms of Parker's.

... p+4 = q = 2k

... (p+4)/2 = k

Now, we can substitute for q and k in the last equation.

... (p+4) +p +(p+4)/2 = 21

... 5/2p +6 = 21 . . . . . . collect terms

... p = (2/5)(21 -6) . . . . subtract 6, multiply by 2/5

... p = 6 . . . . . . Parker is 6 years old

square root

step-by-step explanation:

345

step-by-step explanation: