Question

Add the following expressions:

(i) 5m + 0.3n $-$ 1.2t ; 0.23m $-$ 2.8t + 4n

(ii) $\frac{a}{2}-\frac{7b}{3}+\frac{3c}{4};\frac{5a}{2}-\frac{2b}{3}-\frac{7c}{4}$

Answer 1

$$\begin{gathered} \left(\mathrm{i}\right) \\ \mathrm{We}\mathrm{have}\left(5m+0.3n-1.2t\right)+\left(0.23m-2.8t+4n\right) \\ =5m+0.3n-1.2t+0.23m-2.8t+4n \\ =5m+0.23m+0.3n+4n-1.2t-2.8t \\ =5.23m+4.3n-4t \end{gathered}$$

$$\begin{gathered} \left(\mathrm{ii}\right) \\ \mathrm{We}\mathrm{have}\left(\frac{a}{2}-\frac{7b}{3}+\frac{3c}{4}\right)+\left(\frac{5a}{2}-\frac{2b}{3}-\frac{7c}{4}\right) \\ =\frac{a}{2}-\frac{7b}{3}+\frac{3c}{4}+\frac{5a}{2}-\frac{2b}{3}-\frac{7c}{4} \\ =\frac{a}{2}+\frac{5a}{2}-\frac{7b}{3}-\frac{2b}{3}+\frac{3c}{4}-\frac{7c}{4} \\ =\frac{6a}{2}-\frac{9b}{3}-\frac{4c}{4} \\ =3a-3b-c \end{gathered}$$