1.次の逆数を答えなさい。
(1)\(\displaystyle \frac{3}{4}\)
\(\displaystyle \frac{4}{3}\)
(2)\(\displaystyle \frac{4}{7}\)
\(\displaystyle \frac{7}{4}\)
(3)\(\displaystyle \frac{8}{5}\)
\(\displaystyle \frac{5}{8}\)
(4)\(\displaystyle 0.3\)
\(\displaystyle \frac{10}{3}\)
(5)\(\displaystyle 0.9\)
\(\displaystyle \frac{10}{9}\)
(6)\(\displaystyle 1.4\)
\(\displaystyle \frac{5}{7}\)
(7)\(\displaystyle 1\frac{5}{6}\)
\(\displaystyle \frac{6}{11}\)
(8)\(\displaystyle 2\frac{4}{9}\)
\(\displaystyle \frac{9}{22}\)
(9)\(\displaystyle \frac{1}{3}\)
\(\displaystyle 3\)
(10)\(\displaystyle 0.07\)
\(\displaystyle \frac{100}{7}\)
(11)\(\displaystyle 0.15\)
\(\displaystyle \frac{20}{3}\)
(12)\(\displaystyle 1.23\)
\(\displaystyle \frac{100}{123}\)
(13)\(\displaystyle 1.75\)
\(\displaystyle \frac{4}{7}\)
(14)\(\displaystyle 6\)
\(\displaystyle \frac{1}{6}\)
(15)\(\displaystyle 17\)
\(\displaystyle \frac{1}{17}\)
2.次の計算をしなさい。
(1)\(\displaystyle \frac{5}{7}÷3\)
\(\displaystyle \frac{5}{21}\)
(2)\(\displaystyle \frac{3}{8}÷5\)
\(\displaystyle \frac{3}{40}\)
(3)\(\displaystyle \frac{2}{9}÷7\)
\(\displaystyle \frac{2}{63}\)
(4)\(\displaystyle \frac{3}{11}÷4\)
\(\displaystyle \frac{3}{44}\)
(5)\(\displaystyle \frac{2}{7}÷4\)
\(\displaystyle \frac{1}{14}\)
(6)\(\displaystyle \frac{6}{5}÷3\)
\(\displaystyle \frac{2}{5}\)
(7)\(\displaystyle \frac{14}{15}÷7\)
\(\displaystyle \frac{2}{15}\)
(8)\(\displaystyle \frac{24}{11}÷8\)
\(\displaystyle \frac{3}{11}\)
(9)\(\displaystyle 1\frac{1}{6}÷4\)
\(\displaystyle \frac{7}{24}\)
(10)\(\displaystyle 2\frac{2}{7}÷3\)
\(\displaystyle \frac{16}{21}\)
(11)\(\displaystyle 2\frac{7}{10}÷5\)
\(\displaystyle \frac{27}{50}\)
(12)\(\displaystyle 1\frac{7}{9}÷4\)
\(\displaystyle \frac{4}{9}\)
(13)\(\displaystyle 2\frac{4}{7}÷8\)
\(\displaystyle \frac{9}{28}\)
(14)\(\displaystyle 2\frac{1}{10}÷28\)
\(\displaystyle \frac{3}{40}\)
(15)\(\displaystyle 3\frac{6}{11}÷6\)
\(\displaystyle \frac{13}{22}\)
(16)\(\displaystyle 5÷\frac{3}{7}\)
\(\displaystyle \frac{35}{3}\)
(17)\(\displaystyle 4÷\frac{7}{5}\)
\(\displaystyle \frac{20}{7}\)
(18)\(\displaystyle 11÷\frac{7}{8}\)
\(\displaystyle \frac{88}{7}\)
(19)\(\displaystyle 8÷\frac{9}{4}\)
\(\displaystyle \frac{32}{9}\)
(20)\(\displaystyle 5÷\frac{10}{7}\)
\(\displaystyle \frac{7}{2}\)
(21)\(\displaystyle 6÷\frac{9}{8}\)
\(\displaystyle \frac{16}{3}\)
(22)\(\displaystyle 10÷\frac{8}{7}\)
\(\displaystyle \frac{35}{4}\)
(23)\(\displaystyle 7÷\frac{21}{11}\)
\(\displaystyle \frac{11}{3}\)
(24)\(\displaystyle 6÷1\frac{2}{9}\)
\(\displaystyle \frac{54}{11}\)
(25)\(\displaystyle 7÷2\frac{2}{7}\)
\(\displaystyle \frac{49}{16}\)
(26)\(\displaystyle 4÷2\frac{5}{9}\)
\(\displaystyle \frac{36}{23}\)
(27)\(\displaystyle 14÷2\frac{1}{7}\)
\(\displaystyle \frac{98}{15}\)
(28)\(\displaystyle 7÷1\frac{3}{11}\)
\(\displaystyle \frac{11}{2}\)
(29)\(\displaystyle 12÷2\frac{2}{7}\)
\(\displaystyle \frac{21}{4}\)
(30)\(\displaystyle 39÷2\frac{11}{14}\)
\(\displaystyle 14\)
3.次の問いに答えなさい。
(1)\(\displaystyle \frac{13}{5}\)ℓのジュースを6人の子供たちで等しく分けるとき、1人分のジュースは何ℓになるか答えなさい。
\(\displaystyle \frac{13}{5}÷6=\frac{13}{30}\)
【答】\(\displaystyle \frac{13}{30}ℓ\)
(2)1本の長さが\(\displaystyle 2\frac{5}{8}\)mのリボンがある。このリボンを5人で分けるとき、1人分のリボンの長さは何mになるか答えなさい。
\(\displaystyle 2\frac{5}{8}÷5=\frac{21}{40}\)
【答】\(\displaystyle \frac{21}{40}m\)
(3)9個で\(\displaystyle 2\frac{5}{11}\)kgの缶詰がある。この缶詰1個の重さは何kgになるか答えなさい。
\(\displaystyle 2\frac{5}{11}÷9=\frac{3}{11}\)
【答】\(\displaystyle \frac{3}{11}kg\)
(4)ジュースが\(\displaystyle 3\frac{3}{13}\)ℓある。7人の子供に等しく分けるとき、1人分のジュースは何ℓになるか答えなさい。
\(\displaystyle 3\frac{3}{13}÷7=\frac{6}{13}\)
【答】\(\displaystyle \frac{6}{13}ℓ\)
(5)8cm\(^2\)の長方形がある。縦の長さが\(\displaystyle \frac{13}{5}\)cmのとき、横の長さは何cmになるか答えなさい。
\(\displaystyle 8÷\frac{13}{5}=\frac{40}{13}\)
【答】\(\displaystyle \frac{40}{13}cm\)
(6)19cm\(^2\)の平行四辺形がある。底辺が\(\displaystyle 1\frac{2}{7}\)cmのとき、高さは何cmになるか答えなさい。
\(\displaystyle 19÷1\frac{2}{7}=\frac{133}{9}\)
【答】\(\displaystyle \frac{133}{9}cm\)
(7)砂糖が120gある。この砂糖を1日\(\displaystyle \frac{40}{21}\)gずつ使うとき、砂糖は何日でなくなるか答えなさい。
\(\displaystyle 120÷\frac{40}{21}=63\)
【答】\(\displaystyle 63日\)
(8)横が\(\displaystyle 4\frac{6}{7}\)cm、面積が51cm\(^2\)の長方形がある。縦の長さを求めなさい。
\(\displaystyle 51÷4\frac{6}{7}=\frac{21}{2}\)
【答】\(\displaystyle \frac{21}{2}cm\)