prob. clock loses > 1 min/day, given stats on pendulum

I was wondering if someone could check my work thanks so the question is like so:

The time it takes for a pendulum to complete the one period is simplified by the formula:

T = 2 pi square root (L/g)

...where g is the constant measuring 9.80655m/s^2 and L is the length of the pendulum.

The length of the pendulums from a manufacture are normally distributed with a mean of 10cm and a standard deviation of 0.01 cm. Assuming the at a 10cm pendulum gives the correct time, what is the probability that a clock using one of theses pendulums will lose more than 1 minute a day?

Click to expand...

My work so far:

Standard deviation: 0.01cm
Mean = 10cm
T = 2pi [sqrt] L/g
Time increases by: 1/ 24x 60
……

P(x > 10.014)
= p (z > (10.014 - 10 / 0.01)
= P (Z > 1.4)
Z = 0.919243

Is this correct? Or should I subtract one from thz?

Thank you! :wink: