A golf ball weighs about 45.9 grams. About how many ounces would a dozen golf balls weigh?

2 Answers
Dec 12, 2016

I've set up a conversion equation:

You can just say it out loud what you're trying to do and that will help you write out your ratios.

45.9 grams per 1 ball
1 ounce per 28.35 grams
We have 12 balls

#(45.9g)/(ball)*(1oz)/(28.35g)*12(ball)#

#(45.9cancelg)/(cancel(ball))*(1oz)/(28.35cancelg)*12(cancel(ball))#

#=(45.9*12)/28.35~~19.4oz#

Dec 13, 2016

so the weight of 12 balls is 19.43 ounces rounded to 2 decimal places

Explanation:

Using Matt B's conversion

1 ounce per 28.35 grams
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Determine the weight of 12 balls in grams")#

Given:#" "#1 ball weighs 45.9 grams

Expressing this as a ratio for 12 balls:

#("ball count")/("total weight") = 1/(45.9" grams")#

So for 12 balls we have #(12xx1" balls")/(12xx45.9" grams") = (12" balls")/(color(red)(550.8" grams"))#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#color(blue)("Converting the grams to ounces")#

If 1 ounce is the same weight as 28.35 grams then again by using ratio:

#("ounces")/("grams") ->1/28.35 -=(1-:28.35)/(28.35-:28.35) = (color(green)(1-:28.35))/1#

I have not completed the division on the top yet as this will introduce rounding errors.

So #color(green)("each gram is worth "1-:28.35=" ounces")#, but we have #color(red)(550.8" grams")#

So #" " (12" balls")/(color(red)(550.8" grams")) =(12"balls")/(color(red)(550.8)color(green)(xx1-:28.35))#

#=" "(12" balls")/(19.4285..."ounces"#

so the weight of 12 balls is 19.43 ounces rounded to 2 decimal places