Transferring Data between sheets in a workbook

First, let me say, while I have used Excel for years, I have only used basic functions and some formulas so be kind and keep it simple.

I have a workbook with two sheets of sku numbers. One sheet has sku numbers and prices, the other just has sku numbers but some of the sku numbers on the second list have been broken out by sizes. I need to take the prices from the first list and transfer them to the matching sku numbers on the second including the ones with multiple of the same sku but with prices. Also, not all of the skus from the second list are on the first list so I only need to do the ones that occur on both lists. There are over 3000 on the first list and 14000 on the second. What is the fastest way to accomplish this.

I tried to sort so that all the sku's in both sheets are in the same order then copy and paste the price to the matching sku on the second sheet and then drag the price down through the sizes on the ones that have different sizes (not all of them do) but I know there must be a faster way. Please help!

For example:

Sheet one:
Sku Price
12345 $100
12346 $500
12444 $150
12347 $200

Sheet two:
Sku Price
12345
12345-5
12345-6
12345-7
12346
12444
12347
12347-5
12347-6
12347-7

Copy of website-product-price-update.xlsx

I think I did that right. If so, here is a sample of what I'm trying to do. The prices from the first sheet need to go on the second sheet but not all of the sku's on the second sheet are on the first and the sku's on the second are broken down by size so one sku number/price from sheet one may actually need to be copied 6 times on sheet two, one for each size.

Thanks for any help you can be.

sample.xlsxThank you! Now how do I get the sku numbers that have sizes next to them to read the same as the main sku number. And round them up to so there is no decimal point as the first sheet shows them? See sample in file...

Thank you! Thank you! Thank you!!!