Maths question >_<

• dibilo

  27 Feb 08, 09:46

  1+1*2+1*2*3+1*2*3*4+ ...... +1*2*3*4*5*6*7*8*9

   

  What is the value of the ones digit in this solution?

   

   

  try solving within 5 steps. no calculators.

• eagle

  27 Feb 08, 10:00

  1 + 1*2 + 1*2*3 + 1*2*3*4 + ...

  the 1*2*3*4*5*... all end with zeros because of 2*5, so all are multiples of 10

  thus, 1 + 2 + 6 + 24

  Answer: 3

• dumbdumb!

  27 Feb 08, 10:06

  Originally posted by dibilo:

  1+1*2+1*2*3+1*2*3*4+ ...... +1*2*3*4*5*6*7*8*9

   

  What is the value of the ones digit in this solution?

   

   

  try solving within 5 steps. no calculators.

  you teacher leh!!! dunno?!

• LatecomerX

  27 Feb 08, 10:57

  Originally posted by dumbdumb!:

  you teacher leh!!! dunno?!

  

  How many teachers do we have here?

   

• eagle

  27 Feb 08, 14:56

  Originally posted by dumbdumb!:

  you teacher leh!!! dunno?!

  who say he don't know. Testing this forum useful a not only mah...

• dibilo

  27 Feb 08, 15:33

  lol this is what happens when you teach too much easy maths. Anyway, i major in physics and chem. NOT MATHS!

• eagle

  27 Feb 08, 15:37

  I also don't major in maths! Nor physics

• dumbdumb!

  27 Feb 08, 19:42

  Originally posted by dibilo:

  lol this is what happens when you teach too much easy maths. Anyway, i major in physics and chem. NOT MATHS!

  heh heh