1. **Problem statement:** Find the products for the given pairs of numbers. 2. **Formula:** To multiply decimals, multiply as if they were whole numbers, then place the decimal point in the product so that the total number of decimal places equals the sum of decimal places in the factors. 3. **Part a:** Calculate $21.2 \times 0.02$. - Count decimal places: $21.2$ has 1 decimal place, $0.02$ has 2 decimal places, total 3. - Multiply ignoring decimals: $212 \times 2 = 424$. - Place decimal: $424$ with 3 decimal places is $0.424$. 4. **Part b:** Calculate $2.05 \times 0.004$. - Count decimal places: $2.05$ has 2 decimal places, $0.004$ has 3 decimal places, total 5. - Multiply ignoring decimals: $205 \times 4 = 820$. - Place decimal: $820$ with 5 decimal places is $0.00820$, which simplifies to $0.0082$. 5. **Problem statement:** Find 25% of 60 grams. 6. **Explanation:** - Jada says find $\frac{1}{4}$ of 60. Since 25% = $\frac{25}{100} = \frac{1}{4}$, this is correct. - Andre says calculate $\frac{25}{100} \times 60$, which is the definition of 25% of 60, so this is also correct. - Both methods are equivalent and yield the same result. 7. **Calculate 25% of 60:** $$25\% \times 60 = \frac{25}{100} \times 60 = \frac{1}{4} \times 60 = 15$$ **Final answers:** - a. $0.424$ - b. $0.0082$ - 25% of 60 grams is $15$ grams.