420
Yes, 7 × 420 = 2,940
2940
60
2940
420 = 2940
7 x 400 + 7 x 20 _________ 2940
The best way to do this is to factor both numbers. 2940 = 2 * 2 * 3 * 5 * 7 * 7 3150 = 2 * 3 * 5 * 5 * 7 Now take the ones that are common: 2 * 3 * 5 * 7. That's 210 to check, you can take the unused factors. For 2940 that's 2 * 7 = 14 and 14 * 210 = 2940 For 3150 that's 3 * 5 = 15 and 15 * 210 = 3150 The 14 and 15 also tell us we have it right since they share no common factors.
2940
91114285.7143
400
9 + 2940 = 2949.
The prime factors of 2,940 are: 2, 3, 5, 7