15a² - 22ab - 5b²
15a² - 25ab + 3ab - 5b²
5a(3a) - 5a(5b) + b(3a) - b(5b)
5a(3a - 5b) + b(3a - 5b)
(5a + b)(3a - 5b)
Answer:
Step-by-step explanation:
Complete Questions:
Find the probability of selecting none of the correct six integers in a lottery, where the order in which these integers are selected does not matter, from the positive integers not exceeding the given integers.
a. 40
b. 48
c. 56
d. 64
Answer:
a. 0.35
b. 0.43
c. 0.49
d. 0.54
Step-by-step explanation:
(a)
The objective is to find the probability of selecting none of the correct six integers from the positive integers not exceeding 40.
Let s be the sample space of all integer not exceeding 40.
The total number of ways to select 6 numbers from 40 is
.
Let E be the event of selecting none of the correct six integers.
The total number of ways to select the 6 incorrect numbers from 34 numbers is:

Thus, the probability of selecting none of the correct six integers, when the order in which they are selected does rot matter is


Therefore, the probability is 0.35
Check the attached files for additionals
Answer: 21 & 18
Step-by-step explanation:
Sum of two numbers is 39
Difference is 3
Let the numbers be x & y
X+y=39........equation 1
X-y=3...........equation 2
X=3+y............equation 3
Substitute equation 3 into equation 1
(3+y)+y=39
3+y+y=39
3+2y=39
2y=39-3
2y=36
Y=36/2
Y=18
Substitute for y in equation 2
X-y=3
X-18=3
X=3+18
X=21
The two numbers are 21 & 18
2(-11)-19
-22-19
-41
D is the answer