Question

A boy found the answer for the question
"Subtract the sum of 1/4 and 1/5 from unity and
express the answer in decimals” as 0.45. The
percentage of error in his answer was
(a) (100/11) % (b) 50%
(d) (200/11)%
(c) 10%​

Answer 1

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It is given that the answer 0.45 as the subtration of 1/4 and 1/5 is incorrect.

So, The correct answer will be

$\large= 1 - \frac{1}{4} - \frac{1}{5}$

Take L.C.M. to make the denominators same.

L.C.M. of 4 and 5=20

$\implies \frac{1}{1} \times \frac{20}{20} = \frac{20}{20} \\ \\ \implies \frac{1}{4} \times \frac{5}{5} = \frac{5}{20} \\ \\ \implies \frac{1}{5} \times \frac{4}{4} = \frac{4}{20} \\ \\ \implies \frac{20 - 5 - 4}{20} = \frac{11}{20}$

So the correct answer is $\frac{11}{20} = 0.55$

So, error

$\large\frac{0.55 - 0.45}{0.55} \times 100 = 18 \frac{2}{11} \%$

${\underline{❥ʜᴏᴘᴇ \: ɪᴛ \: ʜᴇʟᴘs \: ʏᴏᴜ.....}}$

Answer 2

Answer:

• REQUIRED ANSWER :)

It is given that the answer 0.45 as the subtration of 1/4 and 1/5 is incorrect.

So, The correct answer will be

$: \implies1 - \frac{1}{4} + \frac{1}{5}$

We have to find out the LCM to make the denominators same.

LCM of 4 and 5

$: \implies \frac{1}{1} \times \frac{20 }{20} = \frac{20}{20} \\ \\ : \implies \frac{1}{4} \times \frac{5}{5} = \frac{5}{20} \\ \\ : \implies \frac{1}{5} \times \frac{4}{4} = \frac{4}{20} \\ \\ : \implies \frac{20 - 5 - 4}{20 } = \frac{11}{20}$

So the answer is 11/20 = 0.55

Error,

$: \implies \frac{0.55 - 0.45}{0.55} \times 100 = 18 \times \frac{2}{11} \%$

Step-by-step explanation:

Hope it helps uh....✌️