Working with Matthew on Converting Units
I don’t know how other people do unit conversions, my family thinks it’s weird, but I think it’s a great way to convert units. It’s the engineer in me. Here’s an example:
I want to convert 8 Football fields to Inches. Or to say it another way: How many inches are in a football field:
First convert football fields to another unit (everyone knows there’s 100 yards in a football field. So we multiply the football fields by 100 yards/ 1 football field which is the same a multiplying it by 1. Since both values are the same only the units change.
8 football fields 100 yards
-------------------- x ----------------
1 football field
we cancel out the units:
8 football fields 100 yards -------------------- x ---------------- 1 football field
We cancel out the football field units and we end up with yards. We can continue to convert them to feet. 1 yard = 3 feet. So we multiply that.
8 football fields 100 yards 3 feet ------------------ x ---------------- x ----------- 1 football field 1 yard
Again, canceling out the units we’re left with feet.
Finally we convert to inches. 1 foot = 12 inches.
8 football fields 100 yards 3 feet 12 inches ----------------- x ----------------- x ----------- x ----------- 1 football field 1 yard 1 foot
And we’re left with 28,800 inches in a football field.
People often wonder do I divide or multiply to get the right number — as long as you orient the units so they cancel out and always multiply, it works great.
