Answer:x=40
Step-by-step explanation:
To find this
8 times the reciprocal of a number
We get
Assume the number is x
8×1/x=2×1/10
8/x=2/10
8/x=1/5
Cross multiply
x=40
Y = -1/2x - 1
Tell me if you need explanation
Answer:
200 people were at the stadium
Step-by-step explanation:
Let us represent the total number of people at the stadium = x
At a football stadium, 5% of the fans in attendance were teenagers. If there were 10 teenagers at the football stadium
Hence:
5% of total number of people = 10 teenagers
5/100 × x = 10
5x/100 = 10
Cross Multiply
5x = 100 × 10
5x = 1000
Divide both sides by 5
5x/5 = 1000/5
x = 200
The total number of people in the stadium is 200
Answer:
5000/750 = 20:3
Step-by-step explanation:
5kg = 5000g
5000:750 (divide by 10)
500:75 (divide by 5)
100:15 (divide by 5)
20:3
Answer:
See answer below
Step-by-step explanation:
The statement ‘x is an element of Y \X’ means, by definition of set difference, that "x is and element of Y and x is not an element of X", WIth the propositions given, we can rewrite this as "p∧¬q". Let us prove the identities given using the definitions of intersection, union, difference and complement. We will prove them by showing that the sets in both sides of the equation have the same elements.
i) x∈AnB if and only (if and only if means that both implications hold) x∈A and x∈B if and only if x∈A and x∉B^c (because B^c is the set of all elements that do not belong to X) if and only if x∈A\B^c. Then, if x∈AnB then x∈A\B^c, and if x∈A\B^c then x∈AnB. Thus both sets are equal.
ii) (I will abbreviate "if and only if" as "iff")
x∈A∪(B\A) iff x∈A or x∈B\A iff x∈A or x∈B and x∉A iff x∈A or x∈B (this is because if x∈B and x∈A then x∈A, so no elements are lost when we forget about the condition x∉A) iff x∈A∪B.
iii) x∈A\(B U C) iff x∈A and x∉B∪C iff x∈A and x∉B and x∉C (if x∈B or x∈C then x∈B∪C thus we cannot have any of those two options). iff x∈A and x∉B and x∈A and x∉C iff x∈(A\B) and x∈(A\B) iff x∈ (A\B) n (A\C).
iv) x∈A\(B ∩ C) iff x∈A and x∉B∩C iff x∈A and x∉B or x∉C (if x∈B and x∈C then x∈B∩C thus one of these two must be false) iff x∈A and x∉B or x∈A and x∉C iff x∈(A\B) or x∈(A\B) iff x∈ (A\B) ∪ (A\C).
