This math topic focuses on fractions, specifically on finding equivalent fractions by determining the missing numerator for two-digit numbers. It involves solving problems that require you to find a numerator that makes two fractions equivalent, given the denominators. Each problem presents a simple fraction (like 1 over some number) and asks for the numerator that equates it to another fraction with the given denominator being a multiple of the numerator in the simple fraction. This set of problems enhances understanding of relationships within fractions and builds skills in manipulating fractional values.