So we need to solve:
3ˣ⁻¹ = 9ˣ⁺²
To do this, we need to have the same base for both sides of the equation.
So let's go with the base of 3.
3² = 9
3ˣ⁻¹ = (3²)ˣ⁺²
3ˣ⁻¹ = 3²ˣ⁺⁴
Since the bases are the same now, we need to get rid of them and we would get:
x - 1 = 2x + 4
Subtract both sides by 2x:
-x - 1 = 4
Add 1 to both sides:
-x = 5
Divide both sides by -1:
x = -5
Just to help you, that formula is saying that 1 mile is equivalent to 5280 feet, i.e. the number of feet is equal to 5280 * number of miles.
So, you know the number of feet = 21,120 and have to convert that into the equivalent number of miles:
f = 5280m => m = f / 5280
m = 21,120 / 5280 = 4 miles
Answer: 4 miles
Answer:
You turn the whole number into a fraction by putting the dominator as 1 and numerator as 3. Multiple 3 and 5 so straight across.
Answer:
Step-by-step explanation:
From the set of 100 with 10 defective microprocessors, the probability of picking a defective one is;
10/100 = 1/10
From the set of 99 remaining and 9 defective microprocessors, the probability of picking a defective one is;
9/99 = 1/11
From the set of 98 remaining and 8 defective microprocessors, the probability of picking a defective one is;
8/98 = 4/49
From the set of 97 remaining and 7 defective microprocessors, the probability of picking a defective one is;
7/97
Adding all 4 probabilities together, we get;
1/10 + 1/11 + 4/49 + 7/97 = 0.345 or 34.5%