4th Grade Math Question of the Day

1. $\frac{13}{18} = 13 \times \frac{1}{18}$
2. $\frac{13}{16} = 13 \times \frac{1}{16}$ (correct answer)
3. $\frac{11}{18} = 11 \times \frac{1}{18}$
4. $\frac{22}{16} = 22 \times \frac{1}{16}$

Explanation: When you see fractions with the same denominator being added or combined, you're working with like fractions. The key insight here is that Tommy's homework is divided into sixteenths, and you can think of each $\frac{1}{16}$ as one piece of the whole. Tommy starts with $\frac{11}{16}$ completed, which means he has finished 11 pieces out of 16 total pieces. When he completes 2 more $\frac{1}{16}$ parts, you simply add those pieces: 11 + 2 = 13 pieces. Since the total homework is still divided into 16 parts, his new progress is $\frac{13}{16}$, which equals $13 \times \frac{1}{16}$. Choice A ($\frac{13}{18}$) incorrectly changes the denominator to 18, but Tommy's homework was always divided into 16 parts, not 18. Choice C ($\frac{11}{18}$) makes the same denominator error and forgets to add the 2 additional parts Tommy completed. Choice D ($\frac{22}{16}$) incorrectly multiplies instead of adding – it shows $11 \times 2 = 22$, but Tommy added 2 parts to his existing 11 parts, he didn't multiply. The correct answer is B: $\frac{13}{16} = 13 \times \frac{1}{16}$. Study tip: When adding fractions with the same denominator, keep the denominator the same and just add the numerators. Also, remember that any fraction $\frac{a}{b}$ can be written as $a \times \frac{1}{b}$ – this helps you see how many unit fractions you have.