minus-squaretimeisart@lemmy.worldtoNo Stupid Questions@lemmy.world•What are the most mindblowing things in mathematics?linkfedilinkarrow-up1·edit-21 year agoMultiply 9 times any number and it always “reduces” back down to 9 (add up the individual numbers in the result) For example: 9 x 872 = 7848, so you take 7848 and split it into 7 + 8 + 4 + 8 = 27, then do it again 2 + 7 = 9 and we’re back to 9 It can be a huge number and it still works: 9 x 987345734 = 8886111606 8+8+8+6+1+1+1+6+0+6 = 45 4+5 = 9 Also here’s a cool video about some more mind blowing math facts linkfedilink
Multiply 9 times any number and it always “reduces” back down to 9 (add up the individual numbers in the result)
For example: 9 x 872 = 7848, so you take 7848 and split it into 7 + 8 + 4 + 8 = 27, then do it again 2 + 7 = 9 and we’re back to 9
It can be a huge number and it still works:
9 x 987345734 = 8886111606
8+8+8+6+1+1+1+6+0+6 = 45
4+5 = 9
Also here’s a cool video about some more mind blowing math facts