The portion of a student’s ballpoint pen that contains the ink is a cylinder with a diameter of 0.400 cm and a height of 11.5 cm. if the ink lasts 7 weeks, what is the volume of ink that the student uses each week?
a) 0.21 cm3.
b) 0.92 cm3.
c) 1.84 cm3.
d) 12.9 cm3.

Option A is correct

0.21

Step-by-step explanation:

Volume of a cylinder(V) is given by:

where,

r is the radius and h is the height of the cylinder respectively.

As per the statement:

The portion of a student’s ballpoint pen that contains the ink is a cylinder with a diameter of 0.400 cm and a height of 11.5 cm.

⇒diameter(d) = 0.400 cm and height(h) = 11.5 cm

We know that:

Diameter(d) = 2(r)

then;

Divide both sides by 2 we have;

or

r = 0.200 cm

Using the formula [1] substitute the given values we have;

Simplify:

V = 1.4444 cubic cm.

It is given that If the ink lasts 7 weeks.

then;

Volume of ink that the student uses each week =

therefore, 0.21 cubic cm is the volume of ink that the student uses each week

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500

set each factor equal to 0

4x-3 = 0

2x-1 = 0

solve for x.

4x-3=0

4x=3

x= 3/4

solve for x. 

2x-1= 0

2x= 1

x= 1/2

eventually after a few more steps, your answer should be 1/2 is less than or equal to x and 3/4 is greater than or equal to x