3 ms·
In some cases its quicker to think of a larger number that's a multiple of 20, then subtract the multiple, E.g. 228? 240 = 12x20, 240-12 = 228. 2337? 2360 = 1
by 8bitsrule 6y ago
In some cases its quicker to think of a larger number that's a multiple of 20, then subtract the multiple,
E.g. 228? 240 = 12x20, 240-12 = 228.
2337? 2360 = 118x20.
- onlyrealcuzzo 6y agoThis is similar to Vedic math, right? https://en.wikipedia.org/wiki/Vedic_Mathematics https://en.wikipedia.org/wiki/Vedic_Mathematics
- imheretolearn 6y agoThe correct way would be to subtract multiple*diff from the answer of the first multiplication. I couldn't point to a reason but I have been using this method since childhood without being taught :)