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15. 4 mathematician has x apples. If he arranges them in rows of 3 one will be left. The same is the case with
5,7,9 apples. But when he arranged them in rows of 11, non will be left. Find the no. of apples.
Ans: 946.
Read Solution (Total 4)
-
- Answer is 946...
x - 1 is a multiple of 3, 5, 7 and 9
lcm(3, 5, 7, 9) = 315
So, the result is one more than a multiple of 315, which is also a multiple of 11... 946 satisfies these conditions... - 13 years agoHelpfull: Yes(23) No(6)
- clearly we need a number which leaves remainder 1 when divided by 3 , 5 , 7 , 9 but divides 11 perfectly.
LCM of 3,5,7,9 = 315
so number is 315Q + 1...... (eq 1)
now 315Q + 1 should be divisible by 11
315Q + 1
= (11*28 + 7)Q + 1
= ( 11 * 28Q ) + (7Q + 1)
now, second part must be divisible by 11 as well
find value of Q for which it satisfies i.e 3
7*3+1 = 22
so, Q = 3
put in eq 1
315 * 3 + 1 = 945 + 1 = 946 Ans - 10 years agoHelpfull: Yes(9) No(2)
- clearly ,the required number would be such that it leaves a remainder of 1 in case of arranging the apples like 3,5,7,9 and no remainder when devided by 11
so such a number is 946. - 13 years agoHelpfull: Yes(6) No(7)
- Lcm of 3, 5, 7 and 9 is =35 x9 =315
The number so required is of the form 315k+1 such that it is divisible by 11
clearly when k =3
we have the number as 946 which is divisible by 11.
Hence, the required number is 946 - 10 years agoHelpfull: Yes(5) No(1)
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