3 ms·
20 cubed is obviously too low. 30 cubed too high. 7 is the only number that, when cubed, ends in 3. 27 it is.
by chasing 4y ago
20 cubed is obviously too low. 30 cubed too high. 7 is the only number that, when cubed, ends in 3. 27 it is.
- camgunz 4y agoYeah this is what I do; what number ^3 gives you a 3: it's 7. Bracket it in the 10s place, try it out.
- yebyen 4y agoI went with "28 sounds about right" then saw it was clearly just a bit too high.
- rich_sasha 4y ago30 cubed is 27,000 or about 35% too much. Thus we solution is about 10% smaller than 30. 27 gets you there.