A room with poor air quality has a particle concentration of 80 units. A fan removes 50% of the remaining particles each hour. What is the particle concentration, in these same units, in the room after 2 hours?

20 units

Step-by-step explanation:

Initial particle concentration = 80 units

Particles removed each hour = 50% of the remaining particles

To find:

Particle concentration after 2 hours = ?

Solution:

Particles removed in 1 hour = 50% of remaining particles

i.e. Particles removed in 1 hour = 50% of initial concentration

Particles removed in 1 hour = 50% of 80 = 40

Particles removed in next 1 hour = 50% of remaining particles

i.e. Particles removed in next 1 hour = 50% of concentration after 1 hour

Particles removed in next 1 hour = 50% of 40 = 20

Total particles concentration removed in 2 hours = 40 + 20 = 60 units

Therefore, particle concentration after 2 hours = Initial concentration - Total particle concentration removed in 2 hours

= 80 - 60 = 20 units

answer: i'm not going to give you the answer, but some hints to work it out.

step-by-step explanation: so, if there is a straight line that means that the line angle is 180°. so we subtract the 2 angle measures provided, (15 and 38) from 180. so the answer is 180 - (38 + 15). (you have to solve the equation)

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers