Question

Round off:​ (i) $578$ to the nearest ten.​

Answer 1

Given, number is $578$.
So , the unit place digit of $578$ is $8$.
[If the digit at one's place is less than $5$ , replace one's digit by $0$, and keep the other digits as they are. Also , if the digit at one's place is $5$ or more than $5$, increase tens digit by $1$ , and replace one's digit by $0$.]
$\because$ $8$ is more than $5$,
So, to round off the given number $578$ to the nearest ten, we increase 7 (tens digit) by 1 and replace 8 (one's digit) by 0.​

$\therefore$$578$ is $580$. ​
Hence, round off of $578$ nearest to ten is $580$.​