how to calculate percent increase in lifespan 10-13-2014d1427

2014-10-13

how to calculate percent increase in lifespan 10-13-2014d1427

just calculate the percentage of increase

An example
(110.1-100.4)/100.4*100 = 9.66%
^This gives the same answer as my first attempt.
So you can just get the ratio, multiply by 100 to make it a percent, and subtract 100. However, it is probably better to think of it like this. Find the amount of increase, and then find what percent that the increase is of the base figure.

1st attempt 10-13-2014d1418 


100.4*y/100 = 110.1 -> y=110.1*100/100.4=109.66


109.66-100=9.66





So I think I would say that the longer living group lives 9.66% longer than the shorter living group.





Does this check out if I double the lifespan?  If the lifespan is doubled, then the group should live 100% longer I think.





200.8/100.4*100=200


200-100 = 100





or


(200.8-100.4)/100.4*100=100


So if the lifespan is doubled, the group lives 1 times greater.  Or you could say the value is 2 times the previous value