<h3>Given</h3>
- Set A: A = {-26, -25, -24, -23, - 22, - 21}
- Set B: B ∈ {x: x is even, x ≥ 6 and x ≤ 20}
<h3>(a) </h3>
<em />
<em>Cardinality means the number of elements in the set.</em>
Cardinality of the set A:
n(A) = 6, since we can count 6 elements.
Set B has even numbers between 6 and 20, both included:
- B = {6, 8, 10, 12, 14, 16, 18, 20}
Then its cardinality is:
<h3>(b) </h3>
To solve this we need to compare the elements of sets A or B with numbers given:
- -22 ∈ A, True ⇒ -22 is listed as element of A
- 6 ∈ B, True ⇒ 6 is listed as element of B
- - 21 ∉ A, False ⇒ - 21 is listed as element of A
- 2 ∈ B, False ⇒ 2 is not listed as element of B
Answer:
(3, 2), (2, 3)
Step-by-step explanation:
x + y = 5
xy = 6
Solve the first equation for x.
x = 5 - y
Substitute 5 - y for x in the second equation.
xy = 6
(5 - y)y = 6
5y - y² = 6
y² - 5y + 6 = 0
Factor.
(y - 2)(y - 3) = 0
y - 2 = 0 or y - 3 = 0
y = 2 or y = 3
Now substitute 2 for y in the first equation and solve for x.
x + y = 5
x + 2 = 5
x = 3
One solution is x = 3; y = 2, or (3, 2).
Now substitute 3 for y in the first equation and solve for x.
x + y = 5
x + 3 = 5
x = 2
Another solution is x = 2; y = 3, or (3, 2).
Answer: (3, 2), (2, 3)
<h3>
Answer:</h3>
<h3>
Step-by-step explanation:</h3>
If Alex cut his wire 18 times, he ended up with 19 equal pieces. He kept 7, so has 7/19 of his 1/3 of the wire.
Bob cut his wire 20 times, so ended up with 21 pieces, of which he kept 9. So he has 9/21 = 3/7 of his 1/3 of the wire.
Claudia kept 1/13 of her 1/3 of the wire, so has the smallest piece.
Bob kept (3/7)·(1/3)·126 cm = 18 cm.
Alex kept (7/19)·(1/3)·126 cm ≈ 15.47 cm.
Bob kept the longest part of the original wire.
Answer:
271.25 gal
Step-by-step explanation:
Assuming the tank is oriented so that the quantity of oil is proportional to depth, the amount remaining is ...
(3 1/2 ft)/(8 ft) × (620 gal) = 271 1/4 gal
Answer:
1. ≈ 12.85
2. 15
3. -38
4. 41 miles
5. 88
Step-by-step explanation:
