Page 19 - NUMINO Challenge_C2

2 Numbers and Number of Digits

Basic Concepts Numbers and Number of Digits

In the consecutive numbers below, there are six numbers and nine digits.
7, 8, 9, 10, 11, 12

The numbers are made using 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.
The number of consecutive numbers is (Last Number) (First Number) 1.
For example, there are 10 5 1 6 consecutive numbers from 5 to 10.
The number of digits in consecutive numbers is:
(Number of 1-digit Numbers) 1 (Number of 2-digit Numbers) 2
(Number of 3-digit Numbers) 3

Example Think of all the numbers from 10 to 999. How many numbers and
digits are there?

Class Notes numbers.

From 10 to 999, there are

Among the numbers between 10 and 999,

there are 2-digit numbers and

there are 3-digit numbers.

There are two digits in a 2-digit number and digits in a 3-digit number.

Therefore, there are 2 3 digits in all.

Try It Again Think of all numbers from 5 to 105. How many numbers and
digits are there?

16 NUMINO Challenge C2