Question

Find the ones digit in the cube of
a) 444
b) 312
c) 57
d) 869 ​

Answer 1

Answer:

Unit place

a) 4

b)8

c)3

d)9

Answer 2

Step-by-step explanation:

⇒ 444^3  ⇒ (440 + 4)^3

⇒ (440)^3 + 4^3 + 3(440*4)(440+4)

    440^3 and 3(440*4)(444) are multiple of 10, it will have 0 at ones digit, we can ignore this for the ones digit of 444^3

⇒ 4^3   ⇒ 64,  ones digit is 4.

⇒ 312^3 = (310 + 2)^3

   As we did in first, same here,

⇒ 2^3  ⇒ 8,   ones digit is 8.

⇒ 57^3 = (50 + 7)^3

    Similarly,

⇒ 7^3    ⇒ 343 ,  ones digit is 3

⇒ 869^3 = (860 + 9)^3

     Same manner,

⇒ 9^3 ⇒ 729      , ones digit is 9