Question

Solve: a) 2/5+ 21/4 ​

Answer 1

• As per the data given in the question, We have to add the two fractions.
• Given data- $\frac{2}{5}+\frac{21}{4}$
• Step 1- We observe the denominator, if the denominator is same, we add the numerator directly over the denominator. if the denominator is not the same, we will take the LCM of denominators to make them same.
• Step 2- After observing we see the denominator is different so we are taking LCM. we will get it,

       $=5\times4=20.$

• Step 3- divide the product of LCM with each denominator and getting quotient will multiply with each numerator and added to it. we will get it,

       $=\frac{4\times2+21\times 5}{20}$

       $=\frac{8+105}{20}$

       $=\frac{113}{20}$

Answer 2

$\dfrac{2}{5} +\dfrac{21}{4} = \dfrac{113}{20} \text{ or } 5.65$

Given:

$\dfrac{2}{5} +\dfrac{21}{4}$

To Find:

Addition of Fractions

Solution:

Create equivalent fractions :

By dividing or multiplying the numerator and denominator of a given fraction by the same number except zero

a/ b  = ak/bk      k ≠ 0

a/b  = (a/k) / (b/k)   k ≠ 0

Step 1:

Change both the fractions so that both have common denominator 20

$\dfrac{2 \times4}{5 \times4} +\dfrac{21 \times5}{4 \times5}$

$\dfrac{8}{20} +\dfrac{105}{20}$

Step 2:

Add the numerators as they have common denominator 20

$\dfrac{8+105}{20} \\ \\\dfrac{113}{20}$

Step 3:

Convert into decimal by long division or multiplying numerator and denominator by 5

5.65

Hence,

$\dfrac{2}{5} +\dfrac{21}{4} = \dfrac{113}{20} \text{ or } 5.65$