Answer:
Isolate the variable by dividing each side by factors that don't contain the variable.
x = w/3 - 2/3
Answer:
a) 0.8333
b) 0.75
c) 0.8181 or 0.9090
Step-by-step explanation:
a)
The probability the visitor selects an authentic painting is
10/12 = 0.8333
b)
Since the opinion of the expert does not depend on your choice, the events are <em>independent</em>, so the probability that the expert says is authentic and it really is, is
0.8333*0.9 = 0.75
c)
If the expert decides the painting is a copy and it is not, then there are 11 paintings of which 9 are authentic, so the probability the visitor selects a new original painting is
9/11= 0.8181
If the expert decides the painting is a copy and it is, then there are 11 paintings of which 10 are authentic, so the probability the visitor selects a new original painting is
10/11= 0.9090
Answer:
20
Step-by-step explanation:
10+10=20
Answer:
60 grams
Step-by-step explanation:
For these type of questions, we can equate the ratio with the actual amounts. We will let the quantity to find be an unknown variable, such as x. Then we equate the ratios, cross multiply, and use algebra to solve.
Let grams of zinc be "x", so we can write the ratios and actual amounts as:

Then we cross multiply and solve for x, what we want to find out. Shown below:

There are 60 grams of zinc.