You need to read the label instructions for coverage to be sure. Typically, a ready mix bag of concrete will cover less than 1 cubic foot (about 2/3), and you have 7 x 10 x 1/2 =35 cubic feet, so you will need 50-60 bags
It works out to about 13.1 bags for every inch deepyou're planning on.
An 80-pound bag of sacked concrete typically yields about 0.6 cubic feet of concrete. A standard 12-inch concrete block has a volume of approximately 0.5 cubic feet. Therefore, an 80-pound bag can fill about 1 to 1.2 blocks, depending on the specific dimensions and any extra material needed for mortar or adjustments.
To determine how many bags of concrete are needed for a slab measuring feet x feet x 4 inches, first convert the dimensions to cubic feet. A 4-inch thickness is equivalent to 0.33 feet, so the volume is calculated as length x width x 0.33. Then, divide the total cubic feet by the volume of a standard bag of concrete (usually 0.5 cubic feet). This will give you the number of bags required.
144
100
18 bags (80 pounds) of quikrete for a 4 inch thick slab.
20
To find out how many yards of concrete you need for your 450 sq ft patio, you would first need to determine the thickness of the concrete you plan to pour. Let's assume a standard 4-inch thickness. One cubic yard of concrete would cover 81 square feet at a 4-inch depth. So for a 450 sq ft patio at 4 inches thick, you would need approximately 5.56 cubic yards of concrete.
It works out to about 13.1 bags for every inch deepyou're planning on.
An 80-pound bag of sacked concrete typically yields about 0.6 cubic feet of concrete. A standard 12-inch concrete block has a volume of approximately 0.5 cubic feet. Therefore, an 80-pound bag can fill about 1 to 1.2 blocks, depending on the specific dimensions and any extra material needed for mortar or adjustments.
2x2
If you use a standard 4-inch thickness you will need a minimum of 6.17 cubic yards.
The number of bags of concrete needed for setting a fence post depends on the size and depth of the hole. Typically, one bag of concrete is enough for a 4-inch diameter post hole that is 2 feet deep. For larger or deeper holes, you may need more bags of concrete. It is recommended to consult a professional or follow the instructions on the concrete packaging for specific guidance.
I assume this might be to keep any dirty ground water from running into the pool.
10 x 10= 100, but divide by 3. 4 inches is one third of a foot. You need 33 and a third cubic feet of concrete. Mixed concrete is usually sold in cubic yards (3 ft x 3ft x3 ft- or 27 cu ft to a cubic yard) and you would need ABOUT 1.25 yards. If you want to mix your own by buying prepackaged concrete mix at the hardware store, you would need ABOUT 112 of the 40 pound bags, or ABOUT 56 of the 80 lb bags. See the link below for a handy calculator for home concrete. PS- sound like you might be pouring a patio or floor for a small shed. Be sure to use reinforcing wire mesh in the floor, or it may crack.
To determine how many bags of concrete are needed for a slab measuring feet x feet x 4 inches, first convert the dimensions to cubic feet. A 4-inch thickness is equivalent to 0.33 feet, so the volume is calculated as length x width x 0.33. Then, divide the total cubic feet by the volume of a standard bag of concrete (usually 0.5 cubic feet). This will give you the number of bags required.
Your slab is slightly over 40 cubic feet. Home Depot sells a 60 pound redi-mix bag which contains 1/2 cubic foot. You will need at least 80 bags. You will need slightly more (maybe 90-100) if you dig you area under the slab unevenly or too deep.