Jack is 13 years older than Bao. In 8 years, he will be twice as old as Bao. How old is Jack now?
+134 So we can express jacks curent age as x, and bao's current age as x-13. It says that 'In 8 years, he will be twice as old as Bao" and we can express that as x+8=2(x-13+8) which we can simplify to x+8=2x-10 from here x=18, so jack is curently 18.
+36916 j = 13 + b and in 8 years j +8 = 2(b+8) (or (j+8)/2 -8=b)
j = 13 + (j+8)/2 - 8
1/2 j = 13 +4-8
j = 18 b = 5 in 8 years j = 26 b = 13
+2094 Let's make two equations!
Let j=Jack's age
Let b=Bob's age
j-13=b
j+8=2(b+8)
--Expand--
j-13=b
j-8=2b
--Subtract equations--
-5=-b
b=5
(Bob is 5 years old now)
18-13=5
So, Jack is 18 years old!
