what is the units of digits of 1!+2!+3!+4!+...50! ?
please help!
thanks!!!!!!!!!
2007-10-04 10:59:20 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
It's 3. The units digits of 5! to 50! are all 0, because
all of these are divisible by 10.
So we only have to look at 1!+2!+3!+4!.
The units digits of each of these are 1,2,6,4
respectively. These add up to 13, so the last
digit of the entire sum is 3.
2007-10-04 11:08:34 · answer #1 · answered by steiner1745 7 · 0⤊ 0⤋
3
three
for series till 4
1! + 2! + 3! + 4!
the sum is 33
after which every factorial is a multiple of 10
so the three in the units digit is taken till any number, not just if its ends at 50!
2007-10-04 11:06:08 · answer #2 · answered by cforcloud 2 · 1⤊ 0⤋
What units would you like? hours, neters, miles, quarts. grams, parsecs, light-years etc? Take your pick. It's your problem.
2007-10-04 11:05:50 · answer #3 · answered by ironduke8159 7 · 0⤊ 2⤋
whats the problem?
2007-10-04 11:02:35 · answer #4 · answered by Anonymous · 0⤊ 2⤋