Answer:
Step-by-step explanation:
Comment
The trick here is to figure out the equations. It is not that they are difficult, but you can't solve the problem without good simple equations.
Let Mrs. Smythe be x
Let Samantha be y
Equations
x = 2*y
Now write the next equation taking into account that it was 10 years ago.
(x - 10) + (y - 10) = 46
Notice the 2 disappeared. That is because you are not trying to describe the relationship between x and y -- only the fact that 10 years ago the sum of their ages was 46.
Now put 2y into the second equation for x.
(2y - 10) + (y - 10) = 46 Remove the brackets
2y - 10 + y - 10 = 46 Combine
3y - 20 = 46 Add 20 to both sides
3y -20 +20 = 46 + 20 Combine
3y = 66 Divide by 3
3y/3 = 66/3
y = 22 Use y to solve for x. (x = 2y)
x = 2y
x = 2*22
x = 44
Answer: Mrs. Smythe is 44 years old.
