Bosco

228 miles on 12 gallons of fuel;240 miles on 10 gallons of fuel     

228 mi on 12 gal  =  19 mi/gal     

240 mi on 10 gal  =  24 mi/gal     

Conclusion:  Either two different vehicles     

                     or a very strong head wind.

_.     

x=1/2(120-45)     

x=-104?     

 Is this right answer? where is wrong?      

  x  =  (¹/₂) (120 – 45)     

  x  =  (¹/₂) (75)     

  x  =  37.5     

_.     

The number of allowable doubtful digits in a measurement or     

the result of mathematical operations with measurements is _____________ .     

A properly recorded measurement or calculation should     

contain only one doubtful (estimated or uncertain) digit,     

which is always the last significant figure. This last digit     

represents the limit of the instrument's precision, with all     

preceding digits assumed to be certain.     

_.     

The lateral area of a right cylinder having a base diameter of 10 units and a height of 10 units is:     

Area_lateral  =  Circumference x Height     

                  =  π d h     

                  = (3.14) (10) (10)     

                  =  314 units²     

_.     

Assume that the moon is a sphere.     

What is the volume of the moon if its diameter is 3,476 km?     

Express your answer in scientific notation to two significant digits.     

Volume_sphere  =  (4/3) π r³     

                        =  (4/3) (3.1416) (1738³)     

                        =  (4/3) (3.1416) (5,249,879,272)     

                        =  21,990,694,294.6  rounds to  2.20 x 10¹⁰ km³     

_.     

The surface area of a sphere having a diameter of 8 inches is:     

Area_sphere  =  4 π r²     

                   =  (4) (3.1416) (4²)     

                   =  (4) (3.1416) (16)     

                   =  201.1  rounds to  201 in²     

_.     

A sphere which has a diameter of 6 inches has a volume of:     

V_sphere  =  (4/3) π r³     

              =  (4/3) (3.1416) (3³)     

              =  (4/3) (3.1416) (27)     

              =  113.1  rounds to  113 in³     

_.