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google search
Google search results:
1: https://www.toppr.com/ask/en-jp/question/i-in-a-family-of-six-persons-a-b-c-d-e-and-f-there-2/
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2: https://www.toppr.com/ask/en-hu/question/in-a-family-there-are-six-members-a-b-c-d-e-and-f-a-2/
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3: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3091824/
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4: https://www.ncbi.nlm.nih.gov/books/NBK215128/
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5: https://www.nytimes.com/interactive/2016/03/23/fashion/weddings/marriage-questions.html
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6: https://www.ets.org/s/gre/pdf/practice_book_psych.pdf
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7: https://journals.sagepub.com/doi/full/10.1177/0361684315590774
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8: https://projects.iq.harvard.edu/files/stat110/files/selected_solutions_blitzstein_hwang_probability_01.pdf
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9: https://fragilefamilies.princeton.edu/sites/fragilefamilies/files/rwjf_program_results_report.pdf
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10: https://www.frontiersin.org/articles/418494
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11: https://books.google.com/books?id=eWQEAAAAMBAJ&pg=PA22&lpg=PA22&dq=There+are+six+members+E,+K,+Y,+D,+O+and+N+in+a+family.+There+are+two+married+couples+in+the+family.+E+is+the+mother+of+D,+N+is%0Athe+father+of+Y,O+is+the+father+of+K+and+is+married+to+E.+D's+gender+is+the+same+as+N's+gender.+E+has+only+one+son.+Y+is+married%0Ato+K.%0A13.%0AThe+question+is+based+on+the+data/information+given+below.+Answer+the+question+by+choosing+the+correct+option+from+the%0Achoices+given.%0AHow+is+Y+related+to+0?&source=bl&ots=h9JhchurJn&sig=ACfU3U1xCsyUF1GUDSIkJFssocIcQ4AQCw&hl=en&sa=X&ved=2ahUKEwiR9Za2xN_yAhVXCM0KHWm-Br0Q6AF6BAgREAM
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