Wykonaj odejmowanie podanych wyrażeń:
a) \( 4\dfrac{1}{2}-1\dfrac{2}{5}\)
b) \( 7\dfrac{5}{6}-4\dfrac{3}{4}\)
c) \( 4\dfrac{2}{3}-4\dfrac{2}{7}\)
d) \( 11\dfrac{9}{13}-5\dfrac{1}{2}\)
e) \( 20\dfrac{5}{14}-13\dfrac{1}{6}\)
Rozwiązanie
a)
\(4\dfrac{1}{2}-1\dfrac{2}{5}=
4\dfrac{1}{2}_{\: / \: \cdot 5}-1\dfrac{2}{5}_{\: / \: \cdot 2}=
4\dfrac{5}{10}-1\dfrac{4}{10}=3\dfrac{1}{10}\)
b)
\(7\dfrac{5}{6}-4\dfrac{3}{4}=
7\dfrac{5}{6}_{\: / \: \cdot 2}-4\dfrac{3}{4}_{\: / \: \cdot 3}=
7\dfrac{10}{12}-4\dfrac{9}{12}=3\dfrac{1}{12}\)
c)
\(4\dfrac{2}{3}-4\dfrac{2}{7}=
4\dfrac{2}{3}_{\: / \: \cdot 7}-4\dfrac{2}{7}_{\: / \: \cdot 3}=
4\dfrac{14}{21}-4\dfrac{6}{21}=\dfrac{8}{21}\)
d)
\(11\dfrac{9}{13}-5\dfrac{1}{2}=
11\dfrac{9}{13}_{\: / \: \cdot 2}-5\dfrac{1}{2}_{\: / \: \cdot 13}=
11\dfrac{18}{26}-5\dfrac{13}{26}=6\dfrac{5}{26}\)
e)
\(20\dfrac{5}{14}-13\dfrac{1}{6}=
20\dfrac{5}{14}_{\: / \: \cdot 3}-13\dfrac{1}{6}_{\: / \: \cdot 7}=
20\dfrac{15}{42}-13\dfrac{7}{42}=7\dfrac{8}{42}\)
a) \( 4\dfrac{1}{2}-1\dfrac{2}{5}\)
b) \( 7\dfrac{5}{6}-4\dfrac{3}{4}\)
c) \( 4\dfrac{2}{3}-4\dfrac{2}{7}\)
d) \( 11\dfrac{9}{13}-5\dfrac{1}{2}\)
e) \( 20\dfrac{5}{14}-13\dfrac{1}{6}\)
Rozwiązanie
a)
\(4\dfrac{1}{2}-1\dfrac{2}{5}=
4\dfrac{1}{2}_{\: / \: \cdot 5}-1\dfrac{2}{5}_{\: / \: \cdot 2}=
4\dfrac{5}{10}-1\dfrac{4}{10}=3\dfrac{1}{10}\)
b)
\(7\dfrac{5}{6}-4\dfrac{3}{4}=
7\dfrac{5}{6}_{\: / \: \cdot 2}-4\dfrac{3}{4}_{\: / \: \cdot 3}=
7\dfrac{10}{12}-4\dfrac{9}{12}=3\dfrac{1}{12}\)
c)
\(4\dfrac{2}{3}-4\dfrac{2}{7}=
4\dfrac{2}{3}_{\: / \: \cdot 7}-4\dfrac{2}{7}_{\: / \: \cdot 3}=
4\dfrac{14}{21}-4\dfrac{6}{21}=\dfrac{8}{21}\)
d)
\(11\dfrac{9}{13}-5\dfrac{1}{2}=
11\dfrac{9}{13}_{\: / \: \cdot 2}-5\dfrac{1}{2}_{\: / \: \cdot 13}=
11\dfrac{18}{26}-5\dfrac{13}{26}=6\dfrac{5}{26}\)
e)
\(20\dfrac{5}{14}-13\dfrac{1}{6}=
20\dfrac{5}{14}_{\: / \: \cdot 3}-13\dfrac{1}{6}_{\: / \: \cdot 7}=
20\dfrac{15}{42}-13\dfrac{7}{42}=7\dfrac{8}{42}\)
Jak obliczyć dodawanie i odejmowanie ułamków zwykłych – zadanie 3 - wyniki