s = (63-35)/2.7023 ≈ 10.362
At this point, we know that 63 is 1.2265*s above the mean, so the mean (m) must be
m = 63 - 1.2265*10.362 = 50.292
Given that the original problem statement uses numbers with 2 significant figures, the answer should be expressed to 2 significant figures.
The mean and standard deviation of the distribution are 50 and 10, respectively.
A check of the probability of 35 in a normal distribution of mean 50 and standard deviation of 10 gives 6.7%, which rounds to 7%. However, the same check for 63 gives 90.3%, a bit higher than the value given in the problem. Thus, you may need to use (m, s) = (50.3, 10.4) to make the numbers work out, even though this level of precision is not really supported by the numbers in the problem.