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3 years ago

Evaluate the summation of 2 n plus 5, from n equals 1 to 12..

1 answer:

4 0

<span>Let f(n) = 2n + 5. Then we must simply calculate (f1), f(2), ..., (f12). And we have that f(1) = 2*1 + 5 <=> f(1) = 7; f(2) = 2*2 + 5 <=> f(2) = 9; f(3) = 2*3 + 5 <=> f(3) = 11. And so on. It's easy to see that the rest of the results will be 13, 15, 17, 19, 21 and so on. So the summation will be S = 7 + 9 + 11 +... + 29 <=> S = 216</span>

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Simplify the complex number i^28 as much as possible.

ella [17]

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2 years ago

An architecture firm creates blueprints for office buildings. Last week, they produced four rectangular blueprints for four diff

Readme [11.4K]

Answer:

The order from greatest to least :

Project B > Project A > Project D > Project C

Step-by-step explanation:

Project A : A 20-inch by 15-inch blueprint with a scale of 1 inch to 4 feet and a projected cost of $22,000.

Scale factor = $\frac{1 inch}{4 feet}$

Length of the office building on blueprint = l =20 inch

Width of the office building on blueprint = b =15 inch

Real length of the office building on blueprint = L

= $\frac{1 inch}{4feet}=\frac{20 inch}{L}$

L = 80 feet

Real width of the office building on blueprint = B

$\frac{1 inch}{4feet}=\frac{15 inch}{B}$

B = 60 feet

Area of the building = $L\times B=80 ft\times 60=4800 ft^2$

Cost of project = $22,000

Cost of project per square foot = $\frac{\$22,000}{4800 ft^2}=4.58 \$/ft^2$

Project B : A 10-inch by 8-inch blueprint with a scale of 1 inch to 8 feet and a projected cost of $25,000.

Scale factor = $\frac{1 inch}{8 feet}$

Length of the office building on blueprint = l =10 inch

Width of the office building on blueprint = b =8 inch

Real length of the office building on blueprint = L

= $\frac{1 inch}{8feet}=\frac{10 inch}{L}$

L = 80 feet

Real width of the office building on blueprint = B

$\frac{1 inch}{8feet}=\frac{8 inch}{B}$

B = 64 feet

Area of the building = $L\times B=80 ft\times 64=5120 ft^2$

Cost of project = $25,000

Cost of project per square foot = $\frac{\$25,000}{5120 ft^2}=4.88 \$/ft^2$

Project C : A 15-inch by 12-inch blueprint with a scale of 1 inch to 6 feet and a projected cost of $27,000.

Scale factor = $\frac{1 inch}{6 feet}$

Length of the office building on blueprint = l =15 inch

Width of the office building on blueprint = b =12 inch

Real length of the office building on blueprint = L

= $\frac{1 inch}{6 feet}=\frac{15 inch}{L}$

L = 90 feet

Real width of the office building on blueprint = B

$\frac{1 inch}{6feet}=\frac{12 inch}{B}$

B = 72 feet

Area of the building = $L\times B=90 ft\times 72ft=6480 ft^2$

Cost of project = $27,000

Cost of project per square foot = $\frac{\$27,000}{6480ft^2}=4.17\$/ft^2$

Project D :An 8-inch by 6-inch blueprint with a scale of 1 inch to 12 feet and a projected cost of $30,000

Scale factor = $\frac{1 inch}{12 feet}$

Length of the office building on blueprint = l = 8 inch

Width of the office building on blueprint = b =6 inch

Real length of the office building on blueprint = L

= $\frac{1 inch}{12 feet}=\frac{8 inch}{L}$

L = 96 feet

Real width of the office building on blueprint = B

$\frac{1 inch}{12feet}=\frac{6 inch}{B}$

B = 72 feet

Area of the building = $L\times B=96 ft\times 72ft=6912 ft^2$

Cost of project = $27,000

Cost of project per square foot = $\frac{\$30,000}{6912ft^2}=4.34\$/ft^2$

Project B > Project A > Project D > Project C

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3 years ago

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Answer:

312.3

Step-by-step explanation:

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2 years ago

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3 years ago