IP1U9 HOT Q5

Find the number that must be added to \(1\) and \(111\) so that the ratio of the former number to the latter number is \(1:11\).

Find the number such that adding \(5\) to it and subtracting \(21\) from it gives two numbers in the ratio \(2:1\), in that order.

Find all possible \(2\)-digit positive whole numbers such that the ratio of this number to the number obtained by switching the ones-digit and tens-digit of this number is \(4:7\).

Find all possible \(3\)-digit positive whole numbers such that its tens-digit is \(0\) and the ratio of the number to the number on its ones-digit is \(51:1\).