What does sum mean in math?

In math, a sum is the result you get when you add numbers together. In 4 + 3 = 7, the 4 and the 3 are the addends, and 7 is the sum. Words such as plus, total, altogether and in all usually signal a sum. A word problem that uses them is asking you to add.

How do you add two-digit numbers with carrying?

Add the ones first, then the tens, and carry a ten whenever the ones reach 10 or more. For 58 + 36, the ones give 8 + 6 = 14, so keep the 4 and carry 1 ten. The tens then give 5 + 3 + 1 = 9 tens. The sum is 94, and a quick estimate of 60 + 40 = 100 shows it is about right.

At what age do kids learn addition?

In many school systems, children learn to add small numbers at about age 4 or 5. They add within 20 at about 6, and add two- and three-digit numbers with carrying at about 7 or 8. The levels here span ages 4 to 9, and a final Olympic level stretches past them with sums of seven large numbers.

Why does my child still count on fingers to add?

Counting on fingers is a normal stage, and many children keep using it for a while after they start adding. To move past it, show them how to start from the bigger number: for 2 + 9, begin at 9 and count 10, 11. Then build facts they simply know, such as the doubles and the pairs that make 10, so the fingers come out less often.

Is this addition practice free, and can I use it in class?

Yes, it costs nothing to play every addition level, from single digits to the Olympic sums, and there is nothing to install or sign up for. In class, start with one sum and collect the different ways pupils split it to reach a ten. Then each pupil plays at their own level. The schools plan, priced per student, comes with a teacher dashboard that shows who is improving.

Math practice · reimagined

Addition Game

In this addition fight, the sums start with two single digits and grow to seven seven-digit numbers at once, at Olympic level. Get the right total in before your rival and the hit is yours; the quicker you type, the harder it lands.

Ages 4–99+ · no download · plays in your browser · 23 languages

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What is addition?

Addition joins two or more numbers into one total, and its sign is plus, +. The numbers you add are the addends, and the total is the sum. Order never changes the answer: 3 + 5 and 5 + 3 both make 8. String 3 red and 5 blue beads, and you count 8 from either end.

Every level of Addition

Example: what is 8 + 5?

8 needs only 2 more to reach 10, so split the 5 into 2 and 3.
Give the 2 to the 8 first, which makes a full 10.
Then add the 3 that is left over: 10 + 3 is 13.
The total is 13, so you type 13 on the keypad.

Learn it step by step

Adding means putting things together and counting how many you have in all.

If you hold 2 pears in one hand and 3 pears in the other, how many pears do you have altogether? Count them: 1, 2… 3, 4, 5. That's 5 pears. So 2 + 3 = 5.

Start at the bigger number and count up — when the total passes ten, keep going: 8 + 5 is 9, 10, 11, 12, 13. Type the total and swing!

Tips and common mistakes

Learn the doubles by heart, like 6 + 6 = 12. A near double is then just one step away: 6 + 7 is 12 plus 1, so 13.
A common mistake is lining up the wrong digits. In 305 + 42, the 4 belongs under the 0, not under the 3, so the sum is 347, not 725.
Roll two dice and race to call out the total before anyone else does. Once that feels easy, add a third die and keep going.

How to play

A sum such as 7 + 6 appears between the fighters, the same one for you and your rival. Type the total on the keypad: the first correct answer lets Garlic land the hit, and a faster answer hits harder. A wrong total stuns you for a moment, and four right in a row unleash a finisher.

— Quick answers —

Addition: the short FAQ

What does sum mean in math?: In math, a sum is the result you get when you add numbers together. In 4 + 3 = 7, the 4 and the 3 are the addends, and 7 is the sum. Words such as plus, total, altogether and in all usually signal a sum. A word problem that uses them is asking you to add.
How do you add two-digit numbers with carrying?: Add the ones first, then the tens, and carry a ten whenever the ones reach 10 or more. For 58 + 36, the ones give 8 + 6 = 14, so keep the 4 and carry 1 ten. The tens then give 5 + 3 + 1 = 9 tens. The sum is 94, and a quick estimate of 60 + 40 = 100 shows it is about right.
At what age do kids learn addition?: In many school systems, children learn to add small numbers at about age 4 or 5. They add within 20 at about 6, and add two- and three-digit numbers with carrying at about 7 or 8. The levels here span ages 4 to 9, and a final Olympic level stretches past them with sums of seven large numbers.
Why does my child still count on fingers to add?: Counting on fingers is a normal stage, and many children keep using it for a while after they start adding. To move past it, show them how to start from the bigger number: for 2 + 9, begin at 9 and count 10, 11. Then build facts they simply know, such as the doubles and the pairs that make 10, so the fingers come out less often.
Is this addition practice free, and can I use it in class?: Yes, it costs nothing to play every addition level, from single digits to the Olympic sums, and there is nothing to install or sign up for. In class, start with one sum and collect the different ways pupils split it to reach a ten. Then each pupil plays at their own level. The schools plan, priced per student, comes with a teacher dashboard that shows who is improving.

More math to master

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