essay 2-3 pages Cost & Estimating
Ssult89
8/17/2020
1
Mathematics Review
LECTURE 2
Fractions, Ratios and Decimals
• Estimating may involve problems involving ratios, fractions or decimals.
• How do you go about solving these problems?
– Having a simplified version is key, i.e., resolving mixed fractions into improper fractions before calculations: 3 ¼ = 13/4
8/17/2020
2
Fractions, Ratios • Convert 41/7 into a mixed fraction
• Convert 8 1/9 into an improper fraction
• Convert 2.833333…into fraction
• Find the unknown values in (3-x)/5 –(x-2)/3 – 2x/5 = ½
• Solve: (1.9 x 0.032)
20 x 0.0038
• Solve for the unknown in √x = (2 +x)/3
• Two similar cylinders A and B have areas in the ratio of 9:16 respectively. Find the volume of B if A is 81 cubic yards.
• The ratio of the length of corresponding sides of two similar rectangular water tanks is 3:5. The volume of the smaller tank is 8.1 cubic yards. Calculate the volume of the larger tank
• The volume of a sphere is 8 cubic feet. What is its surface area
• A metal hemisphere of radius 12 ft is melted down and the liquid is used to construct a cone of base radius 6ft. Find the slant height of the cone.
Fractions, Ratios
• Solve the unknowns in the simultaneous equation
3x + 5y = 9 and 5x + 2y = 16
• A contractor makes an order for 500 bricks and 80 blocks and pays $8,450. In another order of 220bricks and 50blocks, he pays $4310. Find the cost of 1 block and 100 bricks
• A contractor mixed paints A, B, and C. The ratio of A:B = 2:4 and B:C = 5:7. What is the amount of C in a mixture of 200 in quantity.