Laura and her grandmother Ana have just discovered that last year their ages were divisible by 8, and next year they will be divisible by 7. Grandma Ana is not yet a centenarian. What is Laura's age?
Next year, Laura will be 2 years older than she was last year. Therefore, her age last year is a multiple of 8 that, when added to 2, gives a multiple of 7. Let's find this number:

$$
\begin{array}{rlllllllllllll}
\text { multiples of } 7: & 7 & 14 & 21 & 28 & 35 & 42 & 49 & 56 & 63 & 70 & \ldots & 98 & \ldots \\
\text { (multiples of 7) - } 2: & 5 & 12 & 19 & 26 & 33 & 40 & 47 & 54 & 61 & 68 & \ldots & 96 & \ldots
\end{array}
$$

Note that 40 and 96 are the only multiples of 8 less than 100 that appear in the second row. Since Grandma Ana is less than 100 years old, we can conclude that last year she was 96 years old and Laura was 40. Therefore, Laura's current age is 41 years.