Question

Can you help me with this place

Answer 1

The diameter of Keisha's favorite marble is 2.5cm

The radius of the sphere is the half of the diameter : Radius = Diameter/2

Given diameter of marble = 2.5 cm

So, radius = diameter/2

Radius of the marble = 2.5/2

Radius of the marble = 1.25 cm

The general expression for the volume of sphere with radius 'r' is :

`\text{ Volume of Sphere =}(4)/(3)\Pi* radius^3`

So, the volume of one sphere is :

Substitute the value of r = 1.25 cm

`\begin{gathered} \text{ Volume of Sphere =}(4)/(3)\Pi* radius^3 \\ \text{ Volume of Sphere =}(4)/(3)*3.14*1.25^3 \\ \text{ Volume of Sphere = 8.18 cm}^3 \end{gathered}`

As, Keisha take 6 marbles

So, the volume of 6 marbles = 8.18 x 6

Volume of 6 marbles = 49.08 cm³

It is given that : 1 cubic centimeter has the massof 2.6 grams

1 cm³ = 2.6 gm

As the volume of 6 marbles is 49.08cm³

So, The mass of 49.08cm³ = 49.08 x 2.6

The mass of 6 marbles = 127.608 gm

127.608 to the nearest whole number is 128

Mass of the 6 marbles is 128 gm

Answer : 128 gm