The break apart strategy for multiplication involves splitting one of the factors into smaller, easier parts, then multiplying and adding the results. For example, to solve 6 × 7, you can break 7 into 5 and 2, then multiply 6 × 5 = 30 and 6 × 2 = 12, and finally add 30 + 12 = 42.

The doubling and halving strategy for multiplication involves doubling one factor while halving the other to make the problem easier. For example, to multiply 4 × 16, you can double 4 to get 8 and halve 16 to get 8, then multiply 8 × 8 = 64. This keeps the product the same but simplifies the calculation.

The partial products method in multiplication breaks each number into place values and multiplies each part separately. For example, to multiply 23 × 15, you multiply 20 × 10, 20 × 5, 3 × 10, and 3 × 5, then add all the partial products together to get the final answer.

Compensation in multiplication involves adjusting one factor to a nearby easier number, multiplying, and then correcting the result. For example, to multiply 49 × 6, you can think of 50 × 6 = 300, then subtract one group of 6 (6 × 1 = 6) to get 294. This strategy helps make multiplication quicker and simpler.