Question

Walt grew 10 centimetres in 1 year. He is now 1.6. How tall was he 1 year ago?


(SHOW WORKING)

Answer 1

hope it is helpful. please refer this image

Answer 2

Answer:

$1.5x10^{-3}$ km or .0015 km

Step-by-step explanation:

1. So depending on what metric unit you are ending up with, depends on the way you solve it.
2. From what I did I looked for the conversions from cm to inches to get to meters.
3. Now if you are taking physics or is in chemistry learning about scientific notation and conversions between units this should help you out.
4. The way we set up to find the answer so you can show you work is you will be using a division bar.

$\frac{10cm}{}|\frac{.3937in}{1cm}| \frac{1m}{39.370in} = \frac{3.937}{39.370} = .1m$ <-- this would be the set up...

• Now to understand what i just did there if found out how many cm are in inches and inches in meters so put in the conversions in the table/ equation, but you always have to have the same metric units going across from each other as shown above.
• We are trying to find the answer in km in this situation.

1. Once you have it set up like what is shown above you found all the conversions just to get to meters you need to multiply all the top and then the bottom and that's how i got $\frac{3.937}{39.370}$ and then you will end up dividing them two to get .1 meters.
2. Now we are finish with that part we are going to find the answer in km.
3. Start off with the 1.6 meters to get it to km we are going to move the decimal 3 places to the right giving us .0016 km.
4. We are just going to do the same thing to .1 meters and that gives us .0001 km.
5. But the question is asking about how tall he was a year ago and to find that we are going to subtract .0016 with .0001 km which that will give us .0015 km.

And now for the second part of the answer or not the overall answer...

1. In scientific notation the answer would give us $1.5x10^{-3}$
2. To get the 1.5 you just move the decimal back 3 places to the right and that's how we got 1.5 and because the answer is .0015 moving it the 3 spaces we are going to have to no matter what in this situation put the x10 with the equation and put the exponent -3
3. If you were to place it in the calculator with that equation it should give you .0015 as the answer and if not because it's to big you can use the online conversion calculator.

I hope this Helped... :)