the amount of time a certain brand of light bulb lasts is normally distributed with a mean if 1800 hours and a standard deviation of 85 hours. Using the empirical rule, what percentage of light bulbs last between 1630 hours and 1970 hours?

340%

Step-by-step explanation:

at home andrea has 1 2/3 kilograms of rice

step-by-step explanation:

the system of inequalities is

step-by-step explanation:

step 1

find the equation of the dashed line

we have the points

(0,0) and (3,1)

the line passes through the origin, so, is a direct variation

find the slope

the equation of the dashed line is

the solution of the inequality a s the shaded area above the dashed line

therefore

the equation of the inequality a is

step 2

find the equation of the solid line

we have the points

(4,0) and (0,4)

find the slope

the equation of the solid line is

the solution of the inequality b s the shaded area below the solid line

therefore

the equation of the inequality b is

step 3

the system of inequalities is