An important factor in solid missile fuel is the particle size distribution. significant problems occur if the particle sizes are too large. from production data in the past, it has been determined that the particle size (in micrometers) distribution is characterized by f(x) = 3x −4, x> 1, 0, elsewhere. (a) verify that this is a valid density function. (b) evaluate f(x). (c) what is the probability that a random particle from the manufactured fuel exceeds 4 micrometers?

(a) f(x) is a valid density function.

(b)

(c) The probability that a random particle from the manufactured fuel exceeds 4 micrometers is .

Step-by-step explanation:

We know the particle size (in micrometers) distribution is characterized by

(a) For f(x) to be a legitimate probability density function, it must satisfy the following two conditions:

It holds that for all and

Therefore f(x) is a valid density function.

(b) The cumulative distribution function (CDF) F(x) for a continuous rv X is defined for every number x by

Applying the CDF definition we get:

For F(x) = 0, while for

Because f(x) is a piece-wise function, we have

(c) To find the probability that a random particle from the manufactured fuel exceeds 4 micrometers, you need to use the CDF,

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.

9 sandwiches per hour

step-by-step explanation:

when we have a rate, we want a 1 in the denominator

27/3 = 9

27 sandwiches/ 3 hours = 9 sandwiches/hour