b=3
I found this out by subtracting and adding on both sides.
In 24 hours, the worm climbs 5 feet.
7-2= 5 (the worm falls 2 feet every night)
So,
5*8=40
It will take bruce's worm about 8 days to get to the top of the well.
I hope this helps!
~kaikers
The Z-score (z) is calculated according to the formula: z = (x - μ) / σ
Where: x is the raw score value, μ is the mean of the population, σ is the standard deviation of the population.
x = 80, μ = 5, σ = 4
z = (80 - 5) / 4
z = 75 / 4 = 18.7500
Z-score is 18.7500