Type or select your answer, then press "Check". After a correct answer, click the => to advance to the next question.
The common error for with divisibility rules occurs when students don't understand what "the sum of the digits" is. Lets look at 84. The digits are 8 and 4 so the sum is 8 + 4 = 12. Type 12 to move to the next question.
12
Good! Now lets look at 31. The digits are 3 and 1 so the sum is 3 + 1 = __?
4
Right On! Now we're getting somewhere! Let's try 3 digits! 465 = 4 + 6 + 5 What is the sum of the digits for 465?
15
I'd say you're ready to practice. Here we go! What is the sum of the digits for 821?
11
What is the sum of the digits for 6423?
15
What is the sum of the digits for 9168?
24
What is the sum of the digits for 78,983?
35
Well! Wasn't THAT the easiest extra credit for studying you ever earned?