Question

Beatrice built about 1/3 of a sandcastle. Linda built 4/7 of the same castle. What fraction of the sandcastle did they build together?

Answer 1

19/21

Explanation:

It should be easy explanation not so hard here

Step 1 we know it is add we find the LCM which is 21 3x7

Step 2 What u do to denominator do to the numerator 1/3x7 and 4/7x3

we get 12/21 and 7/21

Step 3 add them up! Then you get 19/21

How easy

Answer 2

Find out the what fraction of the sandcastle did they build together .

To prove

Let us assume that the fraction of the sandcastle they build together be x .

As given

`Beatrice\ built\ about\ (1)/(3)\ of\ a\ sandcastle.`

`Linda\ built\ (4)/(7)\ of\ the\ same\ castle.`

Than the equation becomes

`x = (1)/(3) +(4)/(7)`

L.C .M of (3,7) = 21

solving

`x = (7 + 3*4)/(21)`

`x = (19)/(21)`

Therefore the fraction of the sandcastle did they build together be

`x = (19)/(21)`

Hence proved