Question

Good evening! I'm looking for advice on how to correctly apply unit conversions, primarily metric conversions. It seems as if I'm placing them in the wrong position, especially when it comes to word problems.

Thank you!

Answer 1

To explain this question, I will take up few examples to help you understand the conversion better. In case of further doubts you can post a word problem for which you need help.

a) 1 kph to mph

1km=1000m

1 kph=1km/1h=1000m/1h=1000mph

b) 1mph to kph

1km=1000m

So 1m=10^-3km

1mph=1m/1h=10^-3km/1h=10^-3km/h

c) Rose has a stuffed toy of mass 300g. How much does it weigh in i) kg ii) mg? weighs?

Given mass=300g

1 kg=1000g

So Mass in kg=300gx1kg/1000g=0.3 kg

Also 1g=1000mg (mg means milligrams)

So mass in mg=1gx1000mg/1g=1000mg

With this example you must have understood that the new unit needs to be placed in numerator with old unit in denominator during conversion

So mass in mg=1gx1000mg/1g=1000mg

New   old

Mass in kg=300gx1kg/1000g=0.3 kg

  New   old

New in bold and underlined, old in bol and italics

I hope it helped