Assuming you are asking how many times the digit 1 appears when writing the numbers 400 to 500:
It appears in the tens place once (41x where x is any digit 0-9) so there will be 10 occurrences of it here.
It appears in the ones place for every digit in the tens place (4x1) so there will be 10 occurrences of it here.
However, the number 411 has been counted twice, once as 41x and again as 4x1.
Thus the digit 1 will be written 10 + 10 - 1 = 19 times.
400 of them.
400/500 = 400 ÷ 500 = 0.8
200 + 300 200 + 200 + 100
500
8000 ÷ 20 = 400
40. There are 400 numbers between 100 and 500 and one in every ten ends in 5.
400
It is closer to 500.
400 + 500 = 900
(((800 plus 400) plus 400) plus 500) plus 500 = 2600
It is 500.
400 is what percent of 500:= 400 / 500= 0.8Converting decimal to a percentage: 0.8 * 100 = 80%