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.

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.

pretty sure 750 each month!

step-by-step explanation: