17 times table

The 17 times table up to 17 × 12

The 17 times table is 17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204. It goes past the 12 × 12 multiplication chart, so most schools do not require it: the Common Core stops at one-digit facts and England at 12 × 12. For many children it is the hardest table up to 20, because 17 is a prime number with no doubling shortcut, but the 10 + 7 split below makes it manageable. The chart above has every fact, and "Hide answers" turns it into a quick self-check.

Multiplication by 17 as 10 + 7 or 20 − 3

Split 17 into 10 and 7: 17 × 3 = 30 + 21 = 51; 17 × 7 = 70 + 49 = 119. For the bigger facts, going down from 20 can be quicker: 17 × 9 = 180 − 27 = 153. Both ways give the same answer, so a child can check one with the other.

A table with a hidden pattern

17 is a prime number, so the 17 times table has no doubling shortcut. It has a pattern instead: the last digits of 17, 34, 51, 68, 85, 102, 119, 136, 153, 170 are 7, 4, 1, 8, 5, 2, 9, 6, 3, 0. Every digit shows up once. "A ticket costs $17. What do 4 tickets cost?" 17 × 4 = 68.

17 times table games and worksheet

The trainer asks the 17 times table out of order with a keypad. The facts children mix up most are 17 × 6 = 102, 17 × 7 = 119 and 17 × 9 = 153 (112, 109 and 163 are the usual slips), so the game brings a missed fact back two or three questions later until it is right three times in a row. When the round feels easy, take the speed test and then the test for the diploma. The 17 times table worksheet prints 30 problems with the answer key on page 2, and the third sheet practices the trick.

A tip for parents

The 7 times table carries the 17s. If 7 × 8 = 56 still takes a moment, practice the 7s for a few days first; the 17s will feel much easier after that. Ask the facts the other way round too: 7 × 17 is the same as 17 × 7.