russian nesting dolls can be manufactured at a rate of 1.23 an hour.16 dolls have been created already.a box of 60 doll's needs to be filled. how long will it take to fill the box?

Answer 1

Here's another approach - although not necessarily better.

1.23 dolls/hr is 1hr/1.23 dolls, or 0.813 hrs/doll. Then, need 48 dolls, so 0.813 hrs/doll x 48 dolls = 39.024 hrs.

Notice how the "doll" units "cancel" at top and bottom, leaving the needed answer (hours). This is dimensional or unit analysis. Helps when setting up a problem with units, as it indicates whether multiplication or division is involved.

Answer 2

(60-16)/(1.23) = 44/(1.23) = about 35.77 hours

= about 35 3/4 hours

= 35 hours 46 minutes and about 20 1/2 seconds

44 dolls are needed to fill the box

1.23 dolls per hour

1.23/1 = 44/x

x = 44/1.23 = about 35.77236 hours