There are 630 children in a school. For a P.T. drill they have to stand in such a manner that the number of rows is equal to number of columns. How many children would be left out in this arrangement.
Answers
Your Answer:
Given :
No. of students = 630 .
Required to find :
- No. of rows and columns in which students needed to stand .
- No. of children left out ?
solution :
1.)
It is given in the question that there are 630 members in the school .
And they need to be arranged in equal number of rows and columns while they are standing for P.T. drill.
Here they gave one condition stating that
They should have equal number of rows and columns.
so,
Here I am giving you the most easiest technique to solve this type of problems .
Here ,
We apply the rules of squaring and a little bit logic.
Let's coming to the answer :
No. of the students is 630.
Now we need to check whether 630 has any perfect square.
so ,
when we check the square root of 630 we are get a decimal number 25.0998------ (this is a non terminating non repeating decimal ).
so ,
Now try to make a round figure of the decimal number.
It will be 25.
so ,
Simply we can say that
No. of rows = No. of colums = 25.
Therefore,
No. of equal rows and columns are 25.
Now,
we have to find how many students left out the arrangement.
This can be find using a bit of logic.
from the above,
we came to know that no. of rows and columns are 25.
2.)
So , no. of students had stand in P.T. drill = no. of rows × no. of columns
hence, no. of students = 25 × 25
= 625
Hence , no. of students had stand in the P.T. drill is 625.
Hence , no. of students had stand in the P.T. drill is 625.But no. of students in school is 630.
so,
No. of students who were left behind are = 630 - 625
= 5 students.
so,
5 students were left out in this arrarrangement.
Answer:
Let the number of rows and column be, x.
∴ Total number of row and column= x × x = x2 As per question, x2 = 500
x = √500
Hence, 16 children would be left out in the arrangement
Step-by-step explanation: