solve problems involving multiplication and division, including scaling by simple fractions and problems involving simple rates

What this means, in plain words

Scaling makes something a number of times larger or smaller while keeping the proportions the same.

A fraction describes part of a whole, or part of a set, once the whole has been split into equal pieces.

This is problem solving: the maths is met inside a situation, so the first job is working out which operation the question is asking for.