28 times 30 is 840. In symbols: 28 × 30 = 840, and 30 × 28 = 840 too.
28 × 30 means adding 28 to itself 30 times: that is 30 copies of 28, which add up to 840.
28, 56, 84, 112, 140, 168, 196, 224, 252, 280, 308, 336, ... (keep going to the 30th multiple). The 30th multiple of 28 is 840.
28 × 30 = 28 × 30 = 840 = 840.
Halve one number and double the other: 28 × 30 = 14 × 60 = 840.
840 ÷ 28 = 30
840 ÷ 30 = 28
840 is even. Prime factorization: 2 × 2 × 2 × 3 × 5 × 7.
| Multiplication | Answer |
|---|---|
| 27 × 30 | 810 |
| 29 × 30 | 870 |
| 28 × 29 | 812 |
| 28 × 28 | 784 |
| 30 × 30 | 900 |
| 26 × 30 | 780 |
Other numbers? Browse the multiplication table, the squares and cubes or the exponent calculator.