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(Q). (i). Find the total number of factors of 54000
(ii). Sum of all factors of 54000
(iii). Sum of all factors of 54000 that ends with 5.
Solution:-
5400 = 2⁴ × 3³ × 5³

(i). 
∴ total number of factors = (4 + 1)(3 + 1)(3 + 1)
80 Answer

(ii)
Sum of all the factors   =  \frac{{{2^{4 + 1}} - 1}}{{2 - 1}} \times \frac{{{3^{3 + 1}} - 1}}{{3 - 1}} \times \frac{{{5^{3 + 1}} - 1}}{{3 - 1}}
                                         = 31×40×312
                                         = 386880   Answer

(iii).
its factor will end with 5 sonly when it is odd factor ⇒ all the factors of 3³ × 5³ will satisfy the condition. Hence sum of all the factors of 3³ × 5³ is given by  
\frac{{{3^{3 + 1}} - 1}}{{3 - 1}} \times \frac{{{5^{3 + 1}} - 1}}{{5 - 1}}
= 40×156
∴ Required answer = 6240 Answer