Explain why, when we add $\frac{1}{4}+\frac{3}{8}$, we can change both fractions to a common denominator in order to find the sum.
Choose the correct answer below.
AWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{2}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{2}{8}+\frac{3}{8}=\frac{2+3}{8}=\frac{5}{8}$.
BWe can change both fractions to a common numerator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{3}{12}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{3}{12}+\frac{3}{8}=\frac{3}{12+8}=\frac{3}{20}$.
CWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{1}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{1}{8}+\frac{3}{8}=\frac{1+3}{8}=\frac{4}{8}=\frac{1}{2}$.
DWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{2}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{2}{8}+\frac{3}{8}=\frac{2+3}{8+8}=\frac{5}{16}$.
Choose the correct answer below.
AWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{2}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{2}{8}+\frac{3}{8}=\frac{2+3}{8}=\frac{5}{8}$.
BWe can change both fractions to a common numerator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{3}{12}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{3}{12}+\frac{3}{8}=\frac{3}{12+8}=\frac{3}{20}$.
CWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{1}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{1}{8}+\frac{3}{8}=\frac{1+3}{8}=\frac{4}{8}=\frac{1}{2}$.
DWe can change both fractions to a common denominator so that they have equal-sized parts. We can't add different-sized parts. In this case, we can make the parts the same size. We have $\frac{1}{4}=\frac{2}{8}$ and so $\frac{1}{4}+\frac{3}{8}=\frac{2}{8}+\frac{3}{8}=\frac{2+3}{8+8}=\frac{5}{16}$.