what is the cost in dollars for the nails used to build a fence 125 meters long if it requires 30 nails per meter? Assume that 40 nails are sold per box at a cost of 75 cents per box

Question

anonymous · Answer

oh and it has to be solved the factor label or dimensional analysis way

anonymous · Answer

Can explain what factor label and dimensional analysis. I just solved it n got $7.50

anonymous · Answer

oh its like converting units you can google it

anonymous · Answer

30nails Per Meter
$$\frac{ 30nails }{ 1meter }=\frac{ ? }{125meters }$$
Multiply both sides by  125Meters
and meters cancel out

$$125*\frac{ 30nails }{ 1 }=\frac{ ? }{125}*125$$

We get 3750 nails are needed

To find out how many boxes we have to divide by 40

$$\frac{ 3750 nails }{ ? }= \frac{ 40 nails }{ 1box }=\frac{ 3750 nails }{ 40 nails }*1box=93.5boxes$$
  must rounded to nearest whole number

$$\approx 94 boxes$$

$$94*$.75=$70.50$$

So correction on my first attempt

anonymous · Answer

thanks thats exactly what i was trying to get too

anonymous · Answer

you're welcome i put 4 nails on my first attempt instead of 40

anonymous · Answer

oh thats probably why the first one looked weird