Question

73. Life Expectancy Some scientists believe there is a limit to how long humans can live. One supporting argument is that during the past century, life expectancy from age 65 has in creased more slowly than life expectancy from birth, so eventu ally these two will be equal, at which point, according to these scientists, life expectancy should increase no further. In 1900 life expectancy at birth was 46 yr, and life expectancy at age 65 was 76 yr. In 2008, these figures had risen to 78.1 and 83.8, respectively. In both cases, the increase in life expectancy has been linear. Using these assumptions and the data given, find the maximum life expectancy for humans. Source: Science

Answer 1

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1900 (19000 2008 /02) let nmhy of Detminea fhom bth eaien 46 8,78-1 fnd tha ae 78.1-46 32. 0.2972 - 08 108-D sfhe hd the esuation usvg y-y m(M) 0 2972 -0 7 Detomne the frn ase 65 Guetenlmis 20 2972x +46 7.8 0.072 (83.8- 76) mE 0.072 (-0) 0072 +76 Ayfaityarand

=46 0:3972x - 0 072 Xy = 76 ニ-30 O2252 X 33.2a 20 -0.2252 133. Frnd e actal oge this eears, ind y o 2972 133 21)19=96 y639.59 1P 5-59 mon