Question

Answer 1

a \(\dfrac{13}{4}\)

b \(\dfrac{45}{7}\)

c \(\dfrac{3}{2}\)

d \(\dfrac{3}{2}\)

Answer 2

\(a,2+\dfrac{5}{4}=\dfrac{8}{4}+\dfrac{5}{4}=\dfrac{13}{4}\)

\(b,\dfrac{3}{7}+6=\dfrac{3}{7}+\dfrac{42}{7}=\dfrac{45}{7}\)

\(c,\dfrac{25}{30}+\dfrac{12}{18}=\dfrac{5}{6}+\dfrac{2}{3}=\dfrac{5}{6}+\dfrac{4}{6}=\dfrac{9}{6}\)

\(d,\dfrac{5}{12}+\dfrac{3}{4}+\dfrac{1}{3}=\dfrac{5}{12}+\dfrac{9}{12}+\dfrac{4}{12}=\dfrac{18}{12}=\dfrac{3}{2}\)

Answer 3

\(a,\dfrac{2\times4}{1\times4}+\dfrac{5}{4}=\dfrac{8+5}{4}=\dfrac{13}{4}\\ b,\dfrac{3}{7}+\dfrac{6\times7}{1\times7}=\dfrac{3+42}{7}=\dfrac{45}{7}\\ c,\dfrac{25}{30}+\dfrac{12}{18}=\dfrac{3}{2}\\ d,\dfrac{5}{12}+\dfrac{3\times3}{4\times3}+\dfrac{1\times4}{3\times4}=\dfrac{5+9+4}{12}=\dfrac{18}{12}=\dfrac{3}{2}\)

Answer 4

\(2+\dfrac{5}{4}=\dfrac{2}{1}+\dfrac{5}{4}=\dfrac{8}{4}+\dfrac{5}{4}=\dfrac{13}{4}\)

\(\dfrac{3}{7}+6=\dfrac{3}{7}+\dfrac{6}{1}=\dfrac{3}{7}+\dfrac{42}{7}=\dfrac{45}{7}\)

\(\dfrac{25}{30}+\dfrac{12}{18}=\dfrac{5}{6}+\dfrac{2}{3}=\dfrac{5}{6}+\dfrac{4}{6}=\dfrac{9}{6}=\dfrac{3}{2}\)

\(\dfrac{5}{12}+\dfrac{3}{4}+\dfrac{1}{3}=\dfrac{5}{12}+\dfrac{9}{12}+\dfrac{4}{12}=\dfrac{18}{12}=\dfrac{3}{2}\)