Cannot simplify =sum formula

I am trying to create something for my work where I have a list of materials ordered on a regular basis and their prices where I can then enter how many of a certain item were ordered in one week and have the total price calculate at the bottom.

So for example I have
A B C
1 Item A £5.00 1.00
2 Item B £10.00 2.00
3 Item C £15.00 3.00
4
5 £70.00

However I cannot get the formula in 5C to work. I don't use excel often and I've tried the few basic ones I know with no luck! (VALUE!)

So far I have =sum(b1)*(c1)+(b2)*(c2)+(b3)*(c3) etc but I have 89 rows so that's going to get a little long winded!

Is anyone able to help with a simplified version of my =sum*+?!

Many Thanks in advance

Your post does not comply with Rule 1 of our Forum RULES. Your post title should accurately and concisely describe your problem, not your anticipated solution. Use terms appropriate to a Google search. Poor thread titles, like Please Help, Urgent, Need Help, Formula Problem, Code Problem, and Need Advice will be addressed according to the OP's experience in the forum: If you have less than 10 posts, expect (and respond to) a request to change your thread title. If you have 10 or more posts, expect your post to be locked, so you can start a new thread with an appropriate title.
To change a Title on your post, click EDIT then Go Advanced and change your title, if 2 days have passed ask a moderator to do it for you.

Try

Please Login or Register  to view this content.

Adapt ranges to your needs