S values

Question 1

Pelvis S value = 212
80 kV 
320 mA 
139 ms
How would you modify your exposure

Answer 1

mAs is 1/3 of 140
or approximately 1/3 of 150
which would be 50 mAs

s value should be 300-400

would halve the mAs (or maybe a little more)
70ms (or maybe 80) (25 mAs)

Question 2

hand s value = 27
60 kV
100 mA
40 ms

How would you modify your exposure

Answer 2

s value should be 80
normal hand exposure is 60/2.5-3.2

mAs was 4

Would more than halve the mAs 
16 ms (1.6 mAs)