Numbers up to 1,000

Look at the tens digit.

• If it is from 0 to 4, round to the lower hundred.
• If it is from 5 to 9, round to the higher hundred.

For example, 342 rounds to 300, while 367 rounds to 400. Put 0 in the tens and ones places; 950 rounds to 1000.

A digit’s value depends on its place in the number. In a three-digit number, the places from left to right are hundreds, tens and ones.

For example, in 426 the digit 4 means 400, the digit 2 means 20, and the digit 6 means 6. A highlighted 0 has a value of 0.

A digit’s value depends on its place in the number. In a three-digit number, the places from left to right are hundreds, tens and ones.

For example, in 426 the digit 4 means 400, the digit 2 means 20, and the digit 6 means 6. A highlighted 0 has a value of 0.

Look at the ones digit.

• If it is 0, 1, 2, 3 or 4, round to the lower ten.
• If it is 5, 6, 7, 8 or 9, round to the higher ten.

For example, 243 rounds to 240, while 247 rounds to 250. The rounded number ends in 0.

Find the increase at each step by subtracting the first number from the second. Check that the same step works for the other pairs.

Add this step to the last number shown. For example, 120, 140, 160 increases by 20 each time.

Combine the hundreds, tens and ones given. The hundreds give the first digit, the tens the second, and the ones the third.

For example, 300 + 40 + 7 = 347. If there are no tens or ones, put 0 in that place: 300 + 0 + 7 = 307.

The number immediately before is one smaller: subtract 1. The number immediately after is one greater: add 1.

The correct answer lists three consecutive numbers: before, given, after. For example, 299, 300, 301.

Compare the hundreds digits first. If they are the same, compare the tens; if those are also the same, compare the ones.

Choose > if the left number is greater, < if it is smaller, and = if they are equal. The open side of the sign faces the greater number.

Expanded form writes a number as a sum of hundreds, tens and ones.

For example, 583 = 500 + 80 + 3. Use the value of each digit, rather than simply adding 5 + 8 + 3. A digit 0 contributes 0 in its place.

Look at the ones digit.

• If it is 0, 1, 2, 3 or 4, round to the lower ten.
• If it is 5, 6, 7, 8 or 9, round to the higher ten.

For example, 243 rounds to 240, while 247 rounds to 250. The rounded number ends in 0.