Add 11: Addition Facts

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Add 11 combines two ideas, add 10 and add 1, so it rewards children who know both.

Counting on from 11

The answers run 12 to 23, and each is exactly one more than the matching add 10 answer.

Add 10 first, then 1 more: 11 + 6 is 10 + 6 = 16, and 1 more is 17.

The sums 20, 21 and 23 are past nineteen, and the jump into the twenties trips children. Say '10 + 9 = 19, one more is 20'.

Swapping the numbers gives the same answer, so each fact below is learned once and used twice.

Untimed by default. A missed fact shows its answer and comes back later in the round.

One US Letter page, clear in black and white.

10 questions, no timer. At the end you see the score, the facts to practice and a sheet you can print.

Not always as a named family. It is included here because it appears in word problems and helps with the two-digit sums that follow.

Compare it with add 10: the answer must be one higher than 10 plus the same number.