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Two Geometry Questions Please Help! Sorry for all the questions today, trying to get all my classes for this week done today! {4/30/18}

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1) A rectangular floor space in a community center is 40 ft long and 32 ft wide. A volunteer is setting up chairs on the floor space. Each chair needs an area of approximately 4 ft by 5 ft.

Which estimate best approximates the number of chairs that can be set up on the floor space?

A: 20

B: 60

C: 260

D: 320

2) A globe has a surface area of 2700 cm². Andrew wants to estimate the volume of the globe. To do the estimate, he approximates π using 3 in both the surface area and volume formulas for a sphere.

Using this method, what value does he get for the approximate volume of the globe?

Thank you for all of your help I really appriate it. Sorry for all the questions in advanced today I'm trying to get all my classes for this week done today becasue I'm moving this week!

Apr 30, 2018

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Total  Area  =   40 * 32  =  1280 ft^2

Area  occupied by each chair  = 4 * 5  =  20 ft^2

Number of chairs  =    1280  / 20   =     61   ≈   60 chairs

Surface  area  =   4 * 3 *  r^2

2700  =  12 * r^2        divide both sides by  12

225  = r^2         take the positive root

15  = r

So....the volume  is

(4/3) * 3 * r^3   =

4 * (15)^3   =    13500 cm^3

Good luck on the move.....!!!!!   Apr 30, 2018