Question

Take away 5 1/5 from 20 3/4.
1 point
A. 15 7/20
B. 15 9/20
C. 15 11/20
D. 15 13/20

Answer 1

Answer:

20(3/4) - 5(1/5) = 15(11/20)

Step-by-step explanation:

We must take away 5 1/5 from 20 3/4.

Now what we must know is that,

It is easier to do mathematical operations with improper or proper fractions than mixed fractions. It can be done with mixed fractions but we may go wrong most of the time.

So, let's convert mixed fraction to improper fraction,

That is just

[(Denominator × Whole number) + Numerator] ÷ Denominator

Then,

5(1/5) = [(5 × 5) + 1]/5

= 26/5

Similarly,

20(3/4) = [(4 × 20) + 3]/4

= 83/4

Hence, our Question changes to,

Take away (26/5) from (83/4)

Now,

We can only add or subtract if the fractions are like.

To make fractions like, their denominators must be equal. So to make them equal we have to take their LCM

Thus,

LCM (4, 5) = 20

Thus, multiplying to change the denominators to 20.

(26/5) × (4/4) = (26 × 4)/(5 × 4)

= (104/20)

And,

(83/4) × (5/5) = (83 × 5)/(4 × 5)

= (415/20)

You might ask why I multiplied on the numerator and the denominator. It is because the fraction will stay the same only if we multiply with both the numerator and denominator.

Now we can subtract,

Thus,

(415/20) - (104/20)

= (415 - 104)/20

= (311/20)

Converting improper fraction to mixed fraction

= 15(11/20)

Hence,

20(3/4) - 5(1/5) = 15(11/20)

Hope it helped you and believing you understood it....All the best