Question

evaliate the following :
1)-3/5+7/5+7/18
2)-13/8+5/16+-1/4
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Answer 1

➤ Answer :-

${\tt \longrightarrow \dfrac{( - 3)}{5} + \dfrac{7}{5} + \dfrac{7}{18}}$

Convert them into like fractions by taking the LCM of the denominators i.e, 18 and 5.

LCM of 18 and 5 is 90.

${\tt \longrightarrow \dfrac{( - 3) \times 18}{5 \times 18} + \dfrac{7 \times 18}{5 \times 18} + \dfrac{7 \times 5}{18 \times 5}}$

${\tt \longrightarrow \dfrac{( - 54)}{90} + \dfrac{126}{90} + \dfrac{35}{90}}$

${\tt \longrightarrow \dfrac{( - 54) + 126 + 35}{90} = \dfrac{107}{90}}$

${\tt \longrightarrow \dfrac{107}{90} = \boxed{\tt 1 \dfrac{17}{90}}}$

$\Huge\therefore$ The answer is ${\tt 1 \dfrac{17}{90}}$.

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${\tt \longrightarrow \dfrac{( - 13)}{8} + \dfrac{5}{16} + \dfrac{( - 1)}{4}}$

Convert them into like fractions by taking the LCM of the denominators i.e, 8,16 and 4.

LCM of 8,16 and 4 is 16.

${\tt \longrightarrow \dfrac{( - 13) \times 2}{8 \times 2} + \dfrac{5}{16} + \dfrac{( - 1) \times 4}{4 \times 4}}$

${\tt \longrightarrow \dfrac{( - 26)}{16} + \dfrac{5}{16} + \dfrac{( - 4)}{16}}$

${\tt \longrightarrow \dfrac{( - 26) + 5 + ( - 4)}{16} = \dfrac{( - 25)}{16}}$

${\tt \longrightarrow \dfrac{( - 25)}{16} = \boxed{\tt -1 \dfrac{9}{16}}}$

$\Huge\therefore$ The answer is ${\tt - 1 \dfrac{9}{16}}$.

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More to know.................

• While adding or subtracting the fractions, if the given fractions are mixed fractions we should convert them into improper fractions by multiplying the denominator and whole number and then by adding the numerator.
• While adding or subtracting the fractions, if the given fractions are unlike fractions we should convert them into like fractions by taking the LCM of the denominators.
• While adding or subtracting the fractions, if the given fractions are like fractions we can solve them easily.