When positive integer n is divided by 6, the remainder is 5. What is

Question

When positive integer n is divided by 6, the remainder is 5. What is the remainder when 5n is divided by 30?

A. 5
B. 10
C. 15
D. 20
E. 25

TCHRL · Answer

n/6= x + remainder of 5 => n∈

11*5/30 = 55/30 -> remainder of  25 
17*5/30 = 85/30 -> remainder of  25 
 And so on...

Answer E : 25

Ayeka · Answer

n/6 =Quotient + 5 
n can be 11,17,23,29,35.....

Remainder when 5n/30, 
11*5/30=Quotient+25 
17*5/30=Quotient+25 
23*5/30=Quotient+25
........

Answer: E

13swiftness · Answer

n/6= 5 remainder
5n/30= 5n/5*6, 5 and 5 cancels out, shouldn't the remainder still be 5?

Krunaal · Answer

Writing it in general form of remainder: Dividend = Divisor * Quotient + Remainder

n = 6q + 5

5n = 30q + 25

q can be any integer.

if q = 0, then 25/30 will give remainder 25
if q = 1, then 55/30 will give remainder 25
if q = 2, then 85/30 will give remainder 25
......and so on.

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