Addition facts · +9

The Plus 9 Facts

Adding 9: one less than 10. Every question in this game has a 9 in it.

Play the +9 game See the chart

Plus 9 chart

Number + 99 + number
1 + 9 = 109 + 1 = 10
2 + 9 = 119 + 2 = 11
3 + 9 = 129 + 3 = 12
4 + 9 = 139 + 4 = 13
5 + 9 = 149 + 5 = 14
6 + 9 = 159 + 6 = 15
7 + 9 = 169 + 7 = 16
8 + 9 = 179 + 8 = 17
9 + 9 = 18same fact turned around
10 + 9 = 199 + 10 = 19

How to learn the +9 facts

Add 10, take 1

9 + 6: 10 + 6 is 16, and take off 1 for 15. This is the quickest trick in the whole chart.

The ones digit drops by 1

9 + 4 = 13, 9 + 5 = 14, 9 + 6 = 15. The answer's last digit is always one less than the number you added.

Play the plus 9 game

Every question uses 9

Free to play · no signup · works on phones, tablets and computers

Open the game full screen

Quick quiz

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←Plus 8→Plus 10−9Minus 9 factsPrint a drill

Plus 9 FAQ

What's the easiest way to add 9?

Add 10, take 1. 9 + 6: 10 + 6 is 16, and take off 1 for 15. This is the quickest trick in the whole chart.

Does 9 + 7 give the same answer as 7 + 9?

Yes, 16 both ways. Adding works in either order.

Is Sumtown really free?

Yes. The whole game plays free in your browser, with no signup, no ads and no time limit. All fourteen mini games are in it. An iPhone app is on its way, and you can read what it will add.

An app is on its way

We're building a Sumtown app for iPhone with the parts that need a real app: offline play for car rides, a town map that remembers how far your child got, and a parent report on every fact. Until then, the whole game is free right here.

Coming soon on theApp Store