This link should clear things up for you. It's the Food Block Guide on Dr. Sears other website. Follow the easy directions at the top of the page. http://www.drsears.com/foodblockguide.page
Yes, you should eat the blocks in equal amoutns, for instance a 1 block snack would be 1 block P and 1 block C and 1 block F. In actual food this would be 1/4 cup cottage cheese (1P), 1/2 cup grapes (1C), and 3 almonds (1F), OR 1/2 cup plain yogurt (1 P, and 1 C) and 1/2 to 1 tsp. peanut butter (1F). A three block meal (the typical sized meal for you) woudld be 3 blocks P, 3 blocks C and 3 blocks F. With your height and additional weight, if you're doing daily exercise you'd probably do well on 12 blocks daily, which woudl be three meals of 3 blocks each (3P, 3C, and 3F) , and three one block snacks (1P, 1C, 1F each snack).
If you have questions, I'd be glad to help.