PYQ Vault
Bank
Guides
Notes
Mocks
Board
Blog
About
Bank
Guides
Notes
Mocks
Board
NDA · Maths · Permutation & Combination
NDA Permutation & Combination — Formulas 1
Question
1
of 13
1.
Which is the formula for the number of trailing zeros of
n
!
n!
n
!
?
A
Z
(
n
!
)
=
⌊
n
2
⌋
+
⌊
n
4
⌋
+
⌊
n
8
⌋
+
⋯
Z(n!)=\left\lfloor\dfrac{n}{2}\right\rfloor+\left\lfloor\dfrac{n}{4}\right\rfloor+\left\lfloor\dfrac{n}{8}\right\rfloor+\cdots
Z
(
n
!)
=
⌊
2
n
⌋
+
⌊
4
n
⌋
+
⌊
8
n
⌋
+
⋯
B
Z
(
n
!
)
=
⌊
n
5
⌋
+
⌊
n
10
⌋
+
⌊
n
15
⌋
+
⋯
Z(n!)=\left\lfloor\dfrac{n}{5}\right\rfloor+\left\lfloor\dfrac{n}{10}\right\rfloor+\left\lfloor\dfrac{n}{15}\right\rfloor+\cdots
Z
(
n
!)
=
⌊
5
n
⌋
+
⌊
10
n
⌋
+
⌊
15
n
⌋
+
⋯
C
Z
(
n
!
)
=
⌊
n
10
⌋
+
⌊
n
100
⌋
+
⋯
Z(n!)=\left\lfloor\dfrac{n}{10}\right\rfloor+\left\lfloor\dfrac{n}{100}\right\rfloor+\cdots
Z
(
n
!)
=
⌊
10
n
⌋
+
⌊
100
n
⌋
+
⋯
D
Z
(
n
!
)
=
⌊
n
5
⌋
+
⌊
n
25
⌋
+
⌊
n
125
⌋
+
⋯
Z(n!)=\left\lfloor\dfrac{n}{5}\right\rfloor+\left\lfloor\dfrac{n}{25}\right\rfloor+\left\lfloor\dfrac{n}{125}\right\rfloor+\cdots
Z
(
n
!)
=
⌊
5
n
⌋
+
⌊
25
n
⌋
+
⌊
125
n
⌋
+
⋯
Back
Skip