Answer: 6.8 pounds
Step-by-step explanation:
Assuming the weight of a litter of puppies is normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = weight of a liter of puppies.
µ = mean weight
σ = standard deviation
From the information given,
µ = 7.1 pounds
σ = 1.2 pounds
the seller only has the z-score of −0.25, looking at the probability distribution table, the z score corresponding to the 0.25 is
- 0.68
Therefore,
- 0.25 = (x - 7.1)/1.2
Cross multiplying by 1.2, it becomes
- 0.25 × 1.2 = x - 7.1
- 0.3 = x - 7.1
x = - 0.3 + 7.1
x = 6.8
Answer: A. 6.8 is correct
Step-by-step explanation:
a z-score is found by using the formula x=(x-u)/o where z is the z-score, x is the puppy's weight in this case, u is the mean, and o is the standard deviation
-0.25=(x-7.1)/1.2
multiply both sides by 1.2
-0.3=x-7.1
add 7.1 to both sides
6.8=x
This is how we got 6.8! Hope this helps :)
