When a number is halfway between two multiples of one hundred , round to ?

Can someone me and do the problem plz so i can understand it more better

Can someone check if i did this correct. it’s number 4 if you’re wondering.

Avery’s piggy bank has 300 nickels, 450 pennies, and 150 dimes. she randomly picks three coins. each time she picks a coin, she makes a note of it and puts it back into the piggy bank before picking the next coin.