Resol i presenta en resultat en forma de nombre mixt:
- $$5\dfrac{8}{9}+2\dfrac{7}{11}$$
- $$\dfrac{45}{8}-2\dfrac{1}{3}$$
- $$27\dfrac{1}{2}-\dfrac{84}{7}$$
- $$\dfrac{23}{3}+\dfrac{9}{5}$$
Veure desenvolupament i solució
Desenvolupament:
- $$5\dfrac{8}{9}+2\dfrac{7}{11}=(5+2)+\Big(\dfrac{8}{9}+\dfrac{7}{11}\Big)=$$ $$=7+\Big(\dfrac{8\cdot11}{9\cdot11}+\dfrac{7\cdot9}{11\cdot9}\Big)=7+\dfrac{88+63}{99}=7+\dfrac{151}{99}=$$ $$=7+1+\dfrac{52}{99}=8\dfrac{52}{99}$$
- $$\dfrac{45}{8}-2\dfrac{1}{3}=5\dfrac{5}{8}-2\dfrac{1}{3}=5-2+\Big(\dfrac{5}{8}-\dfrac{1}{3}\Big)=3+\dfrac{15-8}{24}=3+\dfrac{7}{24}=3\dfrac{7}{24}$$
- $$27\dfrac{1}{2}-\dfrac{84}{7}=27\dfrac{1}{2}-12=27-12+\dfrac{1}{2}=$$ $$15+\dfrac{1}{2}=15\dfrac{1}{2}$$
- $$\dfrac{23}{3}+\dfrac{9}{5}=7\dfrac{2}{3}+1\dfrac{4}{5}=(7+1)+\Big(\dfrac{2}{3}+\dfrac{4}{5}\Big)=$$ $$=8+\dfrac{10+12}{15}=8+\dfrac{22}{15}=8+1+\dfrac{7}{15}=9\dfrac{7}{15}$$
Solució:
- $$8\dfrac{52}{99}$$
- $$3\dfrac{7}{24}$$
- $$15\dfrac{1}{2}$$
- $$9\dfrac{7}{15}$$