Question

what should we added to the sum of -1/4 and 2/5 to make it 1
(plesse give full answer)​

Answer 1

Answer:

$\frac{17}{20}$

Step-by-step explanation:

Let the number that should be added to the sum of $\frac{-1}{4}$ and $\frac{2}{5}$ to make it $1$ be $x$

⇒ $\frac{-1}{4} + \frac{2}{5} + x = 1$

⇒ $\frac{-5 + 8}{20} +x = 1$

⇒ $\frac{-5 + 8 + 20x}{20} = 1$

⇒ $\frac{3+20x}{20} = 1$

⇒ $3 + 20x = 20(1)$

⇒ $20x = 20 - 3$

⇒ $20x = 17$

⇒ $x = \frac{17}{20}$

∴ The number that should be added to the sum of $\frac{-1}{4}$ and $\frac{2}{5}$ to make it $1$ = $\frac{17}{20}$