Question

5．看誰算得又對又快

$\frac{5}{8}÷\frac{16}{7}÷\frac{14}{11}$	$\frac{19}{26}÷\frac{38}{55}×\frac{5}{11}$	$12÷\frac{3}{5}×\frac{3}{25}$	$\frac{3}{8}$×4÷$\frac{3}{8}$×4
$\frac{5}{8}×\frac{4}{3}+\frac{5}{8}÷\frac{3}{4}$	$\frac{7}{18}$÷$\frac{7}{12}$÷$\frac{7}{10}$	$\frac{1}{2}$÷$\frac{5}{4}$×$\frac{2}{3}$	6÷$\frac{3}{10}$-$\frac{3}{10}$÷6
$\frac{7}{18}$×$\frac{1}{4}$+$\frac{3}{4}$×$\frac{7}{18}$	14×$\frac{5}{7}$÷14×$\frac{5}{7}$

Answer 1

分析 根據(jù)分?jǐn)?shù)四則混合運(yùn)算的順序，按照分?jǐn)?shù)四則運(yùn)算的計(jì)算法則，直接進(jìn)行計(jì)算即可．

解答 解：$\frac{5}{8}÷\frac{16}{7}÷\frac{4}{11}$
=$\frac{5}{8}×\frac{7}{16}×\frac{11}{4}$
=$\frac{385}{512}$；

$\frac{19}{26}÷\frac{38}{55}×\frac{5}{11}$
=$\frac{19}{26}×\frac{55}{38}×\frac{5}{11}$
=$\frac{25}{52}$；

$12÷\frac{3}{5}×\frac{3}{25}$
=$12×\frac{5}{3}×\frac{3}{25}$
=$\frac{12}{5}$；

$\frac{3}{8}×4÷\frac{3}{8}×4$
=$\frac{3}{8}×4×\frac{8}{3}×4$
=16；

$\frac{5}{8}×\frac{4}{3}+\frac{5}{8}÷\frac{3}{4}$
=$\frac{5}{8}×\frac{4}{3}×\frac{5}{8}×\frac{4}{3}$
=$\frac{5}{8}×（\frac{4}{3}+\frac{4}{3}）$
=$\frac{5}{8}×\frac{8}{3}$
=$\frac{5}{3}$；

$\frac{7}{18}÷\frac{7}{12}÷\frac{7}{10}$
=$\frac{7}{18}×\frac{12}{7}×\frac{10}{7}$
=$\frac{20}{21}$；

$\frac{1}{2}÷\frac{5}{4}×\frac{2}{3}$
$\frac{1}{2}×\frac{4}{5}×\frac{2}{3}$
=$\frac{4}{15}$；

$6÷\frac{3}{10}-\frac{3}{10}÷6$
=$6×\frac{10}{3}-\frac{3}{10}×\frac{1}{6}$
=20$-\frac{1}{20}$
=19$\frac{19}{20}$；

$\frac{7}{18}×\frac{1}{4}+\frac{3}{4}×\frac{7}{18}$
=$\frac{7}{18}×（\frac{1}{4}+\frac{3}{4}）$
=$\frac{7}{18}×1$
=$\frac{7}{18}$；

$14×\frac{5}{7}÷14×\frac{5}{7}$
=$14×\frac{5}{7}×\frac{1}{14}×\frac{5}{7}$
=$\frac{25}{49}$．

點(diǎn)評 此題考查的目的是理解掌握分?jǐn)?shù)四則混合運(yùn)算的順序以及它們的計(jì)算法則，并且能夠正確熟練地進(jìn)行計(jì)算．