Question

Gardener has 780 plants. He wants to plant there in such a way that the number of rows and the numbers of columns remains same. Find the minimum number of plants need more for this.​

Answer 1

Gardener will need 4 more plants.

Explanation:

Gardener has 780 plants and wants to plant them in an array of n rows and n columns.

The number of plants needed to do that is:

`n*n=n^2`

He actually has 780 plants, thus it should occur:

`n^2=780`

Taking the square root:

n=27.9

Since n needs to be an integer, we round up n to get

n=28

But
`28^2=784`, 4 more than the actual number of plants, thus:

Gardener will need 4 more plants.

Note: There are other possible results for n. If we set n=29, then
`n^2=841` and Gardener would need 841-780=61 more plants, but the question asked for the minimum number of plants.