it might be because the he doesn't put any test cases for you there so you have to make your own like Test.assert(validate(174), true);
it says "Finally, take that sum and divide it by 10. If the remainder equals zero, the original credit card number is valid", so it's explaining what modulus does, but in the code he puts the actually term modulus there to make it easier for us :)
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it might be because the he doesn't put any test cases for you there so you have to make your own like Test.assert(validate(174), true);
it says "Finally, take that sum and divide it by 10. If the remainder equals zero, the original credit card number is valid", so it's explaining what modulus does, but in the code he puts the actually term modulus there to make it easier for us :)