Birthday paradox

How large must the group of people be so that the probability that two people have a birthday on the same day of the year is greater than 90%?

Correct answer:

n =  41

Step-by-step explanation:

p1=36510.0027  q2=1365364=36510.0027 q3=1(1q2) 365363=1(10.0027) 3653630.0082 q4=1(1q3) 365362=1(10.0082) 3653620.0164  q5=1(1q4) 3653654=1(10.0164) 36536540.0271 q6=1(1q5) 3653655=1(10.0271) 36536550.0405 q7=1(1q6) 3653656=1(10.0405) 36536560.0562 q8=1(1q7) 3653657=1(10.0562) 36536570.0743 q9=1(1q8) 3653658=1(10.0743) 36536580.0946 q10=1(1q9) 3653659=1(10.0946) 36536590.1169 q11=1(1q10) 36536510=1(10.1169) 365365100.1411 q12=1(1q11) 36536511=1(10.1411) 365365110.167 q13=1(1q12) 36536512=1(10.167) 365365120.1944 q14=1(1q13) 36536513=1(10.1944) 365365130.2231 q15=1(1q14) 36536514=1(10.2231) 365365140.2529 q16=1(1q15) 36536515=1(10.2529) 365365150.2836 q17=1(1q16) 36536516=1(10.2836) 365365160.315 q18=1(1q17) 36536517=1(10.315) 365365170.3469 q19=1(1q18) 36536518=1(10.3469) 365365180.3791 q20=1(1q19) 36536519=1(10.3791) 365365190.4114 q21=1(1q20) 36536520=1(10.4114) 365365200.4437 q22=1(1q21) 36536521=1(10.4437) 365365210.4757 q23=1(1q22) 36536522=1(10.4757) 365365220.5073 q24=1(1q23) 36536523=1(10.5073) 365365230.5383 q25=1(1q24) 36536524=1(10.5383) 365365240.5687 q26=1(1q25) 36536525=1(10.5687) 365365250.5982 q27=1(1q26) 36536526=1(10.5982) 365365260.6269 q28=1(1q27) 36536527=1(10.6269) 365365270.6545 q29=1(1q28) 36536528=1(10.6545) 365365280.681 q30=1(1q29) 36536529=1(10.681) 365365290.7063 q31=1(1q30) 36536530=1(10.7063) 365365300.7305 q32=1(1q31) 36536531=1(10.7305) 365365310.7533 q33=1(1q32) 36536532=1(10.7533) 365365320.775 q34=1(1q33) 36536533=1(10.775) 365365330.7953 q35=1(1q34) 36536534=1(10.7953) 365365340.8144 q36=1(1q35) 36536535=1(10.8144) 365365350.8322 q37=1(1q36) 36536536=1(10.8322) 365365360.8487 q38=1(1q37) 36536537=1(10.8487) 365365370.8641 q39=1(1q38) 36536538=1(10.8641) 365365380.8782 q40=1(1q39) 36536539=1(10.8782) 365365390.8912 q41=1(1q40) 36536540=1(10.8912) 365365400.9032 q42=1(1q41) 36536541=1(10.9032) 365365410.914 n=41



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