Question

Jack is 13 years younger than his older brother, Tyler. Their Dad is twice Tyler's age. The sum of their ages now is 91. Find Jack's present age.

Answer 1

Answer:

13 years old

Step-by-step explanation:

So to solve this we use a system of equations. Let's use "j" to represent Jack, "t" to represent Tyler, and "d" to represent the dad. Set the system up and it will look something like this:

j = t - 13 (Jack is 13 years younger than Tyler)

d = 2t (Dad is twice Tyler's age)

d + j + t = 91 (The sum of the ages is 91)

And then solve, I solved by isolating the "j" variable on the last equation, giving us j = 91 - t - d, then plugged that into the first equation, giving us 91 - t - d = t - 13, and got d = 104 - 2t. Then I plug that into d = 2t, giving us 104 - 2t = 2t, and solve for t. T is 26, meaning Tyler is 26 years old, and then I just subtract 13 from that, giving us 13 years old.

And finally, I obviously checked my answer, because now we know dad is 52, and I got 91.