n ! = 5 × 5 × 5 − 5
What is the value of n ?
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5x5x5-5 reduces to: 5(5^2-1) Factoring gives 5(6)(4) Since prime factorization of 6 is 2x3, then this becomes 2x3x4x5, which is 5!.
Simple standard approach.
By BODMAS, n ! = 1 2 0 or n = 5 .
This is a factoral method:
n ! = 5 ⋅ 5 ⋅ 5 − 5 ⇒ n ! = 1 2 5 − 5 ⇒ n ! = 1 2 0 .
You don't have to think a number for factoral to find the value of n you have to find form 0 to 9 to find the equal figure.
We have to try:
For 2 : let n = 2 So
n ! = 1 2 0 ⇒ 2 ! = 1 2 0 ⇒ 2 = 1 2 0 2 ! = 1 ⋅ 2 ⇒ 2 ⇒ 2 = 1 2 0
For 4 : let n = 2 So
n ! = 1 2 0 ⇒ 4 ! = 1 2 0 4 ! = 1 ⋅ 2 ⋅ 3 ⋅ 4 ⇒ = 2 4 ⇒ 2 4 = 1 2 0
For 5 : let n = 5 So
n ! = 1 2 0 ⇒ 5 ! = 1 2 0 5 ! = 1 ⋅ 2 ⋅ 3 ⋅ 4 ⋅ 5 ⇒ 1 2 0 ⇒ 1 2 0 = 1 2 0
∴ We found the value of the n that makes the 1 2 0 = 5 ! . So the n = 5
FIN!!!!
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5x5x5-5=120
120÷2=60
60÷2=30
30÷2=15
15÷3=5
5÷5=1
1x2x3x(2x2)x5=5!