Ascending order (smallest time biggest)
0.7 = 70%
31/40 = 77.5%
78% = 78%
Hope this is what you were looking for...
You always get from one term to the next by adding 6:
So, the rule is "add 6"
Suppose s and h are the mileage numbers for the SUV and Hybrid, respectively. Then if each vehicle drives 1 mile, the total gas consumption is
.. 1/s +1/h
Then the combined mileage is
.. 2/(1/s +1/h) = 2sh/(s+h)
Option 1: s=12, h=60
.. mpg = 2*12*60/(12+60) = 20
Option 2: s=11, h=75
.. mpg = 2*11*75/(11 +75) = 1650/86 ≈ 19.2
In summary,
.. Option 1: 20.0 mpg
.. Option 2: 19.2 mpg
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It usually works out best to increase the efficiency of the least-efficient contributor, as here.
