Answer:
the third option
Step-by-step explanation:
what does that mean ?
to "rationalize" it is to transform it into a rational number (that is a number that can be described as a/b, and is not an endless sequence of digits after the decimal point without a repeating pattern).
a square root of a not square number is irrational (not rational).
so, what this question is asking us to get rid of the square root part in the denominator (the bottom part).
for this we need to multiply to and bottom with the same expression (to keep the whole value of the quotient the same) that, when multiplied at the bottom, eliminates the square root.
what can I multiply a square root with to eliminate the square root ? the square root again - we are squaring the square root.
so, what works for 9 - sqrt(14) as factor ?
we cannot just square this as
(9- sqrt(14))² = 81 -2sqrt(14) + 14
we still have the square root included.
but remember the little trick :
(a+b)(a-b) = a² - b²
without any mixed elements.
so, we need to multiply (9-sqrt(14)) by (9+sqrt(14)) to get
81-14 = 67 which is a rational number.
therefore, the third answer option is correct.
Answer:
33.29
Step-by-step explanation:
A=πr^2
A=π2^2=12.57
12.57/2=6.29
7-4=3
3x2=6
6/2=3
4x6=24
6.29+3+24=33.29
39/10 I’m not sure! Use the app called photo math
Answer:
a. Discrete probability distribution, frequent rider club, 0.65 of 20
b. 13
c. $60
d. $57.50
Step-by-step explanation:
a. X follows a discrete probability distribution because it involves discrete random variables which have probability mass function and frequency.
f(x) =0.65 of 20 passengers
b. if 0.65 0f 20 passengers are frequent riders,
then, the frequent riders will be 13 passengers
c. expected revenue will be $3 *20 passengers which will be $60.
the total number of passengers given tickets is 20 and the price for each is $3. thus, making the parameters to be price and number of passengers.
d. if the frequent riders are charged $2, then the amount paid by this group will be $2*13 which is $26
and if $4.50 is paid by the regular passengers it will be $4.50*(20-13) which is $31.50.
therefore, expected revenue will be $26+$31.50 equals $57.50