j = m+4 = 8+d
mp = 16+jd
clearly, Jack is not a twin with either Mark or David.
So, Paul is one of the twins. Either
p=j or p=m or p=d
See what you can do with that. You now will have three equations in three variables, after getting rid of p.
Jack is four years older than Mark and eight years older than Dave. The product from Mark's and Paul's age is greater by 16 than the product from Jack's and Dave's ages. In this group of 4 children, two of them are twins. Who are the twins? What is the age of each of the four boys?
2 answers
Mark's age = X years.
Jack's age = X+4 years.
Dave's age = (X+4)-8 = X-4 years.
J*D = (x+4)(x-4) = x^2-16.
a. M*P = (x+4)(x-4)+16 = x^2-16+16=X^2
= x*x. Therefore, Mark and Paul are each X years old and twins.
Jack's age = X+4 years.
Dave's age = (X+4)-8 = X-4 years.
J*D = (x+4)(x-4) = x^2-16.
a. M*P = (x+4)(x-4)+16 = x^2-16+16=X^2
= x*x. Therefore, Mark and Paul are each X years old and twins.
1 answer