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Question

unicornpoopcookies · Answer

If your annual salary is $36,575,What is your weekly salary?

I first divided 36,575 by 12 (months) and got 3047,91,then divided 3047,91 by 52 (number of weeks) and got 58.61,is this correct?

anonymous · Answer

What seems to be the problem here is that you found the number of weeks in a year rather than in a month for the second part. If you divide by 52 after dividing by the 12 months, you're essentially saying that there are 52 weeks in each of those 12 months. To find the actual answer, you'd divide the original by 52 instead.

whpalmer4 · Answer

Here's my secret for successful unit conversions (which is all this problem is, really): write it out as fractions with the units included.  So if we wanted to instead find your daily salary, here's how I might go about it:

$$$36,575/yr * 1 yr/365 \text{ day} = $36,575 /\cancel{ yr} * 1 \cancel{ yr} / 365 \text{ day} = $$$$$36,575/365 \text{ day} = $100.21/\text{ day}$$

unicornpoopcookies · Answer

so 36,575 divided by 52 = 703.36 is what would be earned weekly?

whpalmer4 · Answer

Yes, ignoring any rounding issues.

unicornpoopcookies · Answer

@whpalmer4 im copying that to my notes RIGHT NOW! (chart)

whpalmer4 · Answer

The beauty of doing the units like this is that it catches your mistakes.  Say you set it up wrong, and did

$$$36,575/yr * 12 mo/1 yr = $36,575*12 mo/yr^2 = $438900 mo/yr^2$$You look at the result, and start scratching your head, because you were expecting $/mo for a unit.  The fact that the units came out wrong is a very strong indicator that the number is also mostly likely incorrect.

whpalmer4 · Answer

It's a bit more work, to be sure, and it's certainly a PITA to typeset neatly in OS (I let that part be a bit messy rather than do it perfectly), but I figure it is an easy way to stack the deck in your favor.

whpalmer4 · Answer

There are some interesting formulas in physics that can be derived almost entirely by reasoning about the units!

unicornpoopcookies · Answer

Both helpful,thank you so much for that chart i dont feel so confused about this anymore!

anonymous · Answer

whpalmer has the right idea. And he is very correct about the Physics derivations. Great job at explaining.