<h3>
Answer: 5/19</h3>
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Explanation:
There are A = 10 red cards out of B = 10+10 = 20 cards total.
A/B = 10/20 = 1/2 represents the probability of picking a red card.
After that card is selected, there are C = 10 black cards out of D = 20-1 = 19 cards left. The fraction C/D = 10/19 represents the probability of picking a black card where we did not put the first red card back.
Multiply the two fractions we found.
(A/B)*(C/D) = (1/2)*(10/19) = 10/38 = 5/19 is the probability of getting the first card that is red and the second card that is black.
Answer:
The equation relates the variables is y = 8x ⇒ D
Step-by-step explanation:
If x and y vary directly (y ∝ x), then y = k x, where
- k is the constant of variation
- k can be found using the initial value of x and y
∵ The variable x and y vary directly
∴ y ∝ x
→ By using the rule above
∴ y = k x
∵ y = 40 when x = 5
∴ The initial values of x and y are x = 5 and y = 40
→ Substitute them in the equation above to find k
∵ 40 = k(5)
∴ 40 = 5k
→ Divide both sides by 5
∵
= 
∴ 8 = k
→ Substitute the value of k in the equation above
∴ y = 8x
∴ The equation relates the variables is y = 8x
Step-by-step explanation:
To find the equation of a line given a point and a parallel line we must use point-slope form.
y - y1 = m(x - x1)
When we plug into this, we use the point in for (x1, y1) and the slope of the parallel line as m.
The probability of a seed not growing into a healthy plant is 1 - 0.8 = 0.2.

The answer is the probability = 0.66 or 6.6%