@Omkarp said:Arey woh ek divide by 2 wala factor bhi tha which I forgot to add in my last post.Or another way is to select two out of the 10 people the number of ways will be 10*9, because idhar order vital hai.. Anyway..Waise probability wale ka Official explanation kya hai??For the abcdef wala question,abcdef aur defabc ka digit sum equal hoga.abcdef*k = defabc hai. We know that multiplication by 9 does not affect the digit sum.So k = 9. defabc is a multiple of 9, matlab uska digit sum will be a multiple of 3. That means abcdef ka digit sum is also a multiple of 3.So, 3*9 = 27.
@Enigma001 said:Why can't the answer be 36?...please explain.
Mere explanation main clearly 3*9 likha toh hai..
@Enigma001 said:Why can't the answer be 36?...please explain.
Options main ek hi tha, so 27..
54 ya kuch aur hota toh issue aa jaata..
Lekin 54 se zyada nahi hota..
Aur 54 hota toh the number would've been 999999.... Toh isko multiply karoge toh 7 digit number aayega, toh necessarily 27 hoga.
@nits2811 said:
A six-digit natural number abcdef becomes defabc upon being multiplied by a natural number. Find the sum of its digits if they are distinct.
20
24
27
36
142857 * 6 = 857142
@Omkarp said:Explanation main gandh machayi thi..so editing..1 - (10/10C2)Last time I successfully managed to confuse myself. Waise probability wale ka Official explanation kya hai??For the abcdef wala question,abcdef aur defabc ka digit sum equal hoga.abcdef*k = defabc hai. We know that multiplication by 9 does not affect the digit sum.So k = 9. defabc is a multiple of 9, matlab uska digit sum will be a multiple of 3. That means abcdef ka digit sum is also a multiple of 3.So, 3*9 = 27.
@nits2811 said:
Ten persons are seated around a circular table. Two of them exchange their places. What is the probability that the two persons who exchange their places, are not sitting side by side?
7/9
2/9
4/5
1/9
take first person. now other person can be selected in 9 ways and person who is not his neighbour in 7 ways so
7/9
@Omkarp said:Numbers kaise find kiye?
abc/def = (1000-n)/(1000n-1)
now n cannot be more than 9 only n=6 satisfies and gives abc/def = 994/5999= 142/857
@nits2811 said:yehi joh tumne likha h...probability walen ka wahi h explanation..waise easy method joh maine socha tha woh batata huun...ek ko choose kar lia...toh now 9 are left usme se do ko chod ke baaki koi bhi exchange kar sakta h so 7/9...xplanation kuch samaj nhi aaya...plss cum again..
Dekho, this other dude has found the exact numbers.
My approach is,
See when you multiply any number by any multiple of 3, the digit sum remains unchanged.
Ab question main likha hai abcdef*k = defabc.
And both sides ka digit sum equal hai..
Matlab k is a multiple of 3.
That means defabc is a multiple of 3.
That means abcdef is a multiple of 3.
That means abcdef*k = defabc is a multiple of 9.
That means abcdef is a multiple of 9, and hence defbca is a multiple of 27.
So, the sum of the digits will be a multiple of 27.
Each of the six people €“ Akshita, Babita, Chintan, Devina, Engela and Farooq €“ works in a different department among Marketing, Finance, Operations, Academics, IT and HR and belongs to a different city among Dhaka, Kashipur, Meerut, Bikaner, Jaipur and Pune, in no particular order. It is also known that:
(i) The person who works in Operations belongs to Kashipur. (ii) Neither Akshita nor Devina belongs to Bikaner. (iii) Akshita works in neither IT nor Marketing. The same is true for Farooq. (iv) Devina works in HR and belongs to neither Jaipur nor Pune. (v) Babita belongs to Dhaka and doesn €™t work in Finance. (vi) The person who works in Academics belongs to neither Jaipur nor Pune. The same is true for the person who works in Finance.
39. Who works in Operations? (a) Akshita (b) Chintan (c) Engela (d) None of these
40. Who works in Finance? (a) Akshita (b) Chintan (c) Engela (d) Farooq
41. The person who works in Academics belongs to which city? (a) Jaipur (b) Dhaka (c) Meerut (d) None of these
@nits2811 said:yehi joh tumne likha h...probability walen ka wahi h explanation..waise easy method joh maine socha tha woh batata huun...ek ko choose kar lia...toh now 9 are left usme se do ko chod ke baaki koi bhi exchange kar sakta h so 7/9...xplanation kuch samaj nhi aaya...plss cum again..
Answer will be 1-2/9=7/9...
@abhi_14 said: @ash1615 : yes bro....cud u pls xplain the approach u followed..i got stuck in this questn...
@abhi_14 said: @ash1615 hmm...actually to figure out tht A connection with kashipur, i took a long tym...wasted around 12-15 mins it....anyways cud u pls share the criss-cross table u made fr this questn..may b u cn upload a pic...
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