Maths metric conversions

I was learning to convert measurements.

the thing I found hard was that the instructions that they gave you was unclear.

what is said was 1km= 1000m 1m = 100cm 1cm = 1000mm

I got confused because first it said 1cm = 1000mm when 1 cm is actually 10mm.

Second i didn't know how I was meant to figure out 3cm = ____km with what it told me.

But thankfully the answer sheet was on the other page.

So I looked at a random question which was 0.2m = _____km, changed it to 0.5m = ____km

and then googled it. the answer was 0.0005.

so I immediately came to a conclusion that I had to just add 3 zeros to the front of the number.

Because I had to change m into km and km = 1000m and that has 3 zeros.

maths trial and error

learning outcome
we are learning to solve a problem by trial and error

success criteria
I will have tried different ways of solving the problem
I will check to see if there is more than one way
I will have a correct answer

the reflection
the problem was that we had 7 cards with a 3, =, 5, x, +, 7, 8, and with those cards we had to make a question that makes sense.
we tried about 7 times we didn't have any clue what the answer was and I thought it was impossible then I remembered the = doesn't always have to be in the middle. so I put it at the end.