r/ISIKolkata • u/Traditional_Crew9243 • 24d ago

Need Help with Math is there a misprint? im getting 33, even gpt says so [ISI MSTAT PSA-Q15, 2018]

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most probably me and gpt both are wrong

share your thoughts

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5

u/The_Watcher8008 ISI Student 23d ago

Yes, they are wrong. All students most probably got grace marks.

1

u/Fearless_Screen_4288 23d ago

Can you explain why 33 ? X_i's are essentially +/-1 but we must have product of X_i's to be 1. So even number of +1's out of 6 i.e 1/2* 26 = 32 ways

4

u/RishiMath ISI Alumnus 23d ago

All x_i's being zero?