Question 1143095
The most probable number is 100*0.75 or 75

for 72, it is 100C72*0.75^72*0.25^28=0.0701

use normal approximation for 70 to 78 but could use the above approach 9 times and add.

mean is 75 
variance is 75*.25=18.75
sd is sqrt (V)=4.33
for 70, use correction factor of 69.5
z=(69.5-75)/4.33 or -1.27
and 
z=(78.5-75)/4.33=+0.81
that probability is 0.6890