Question 1195369
z=(p1-p2)/sqrt(P(1-P)((1/n1)+(1/n2))
P=(316+315)/(453+477)=0.6785 pooled proportion
z=(0.038) sqrt [/(0.6785*0.3215)((1/453)+(1/477))]
=0.038/0.0306
z=1.240

p-value is 0.2150. Where this is rounded will change the z-value. The calculator will give 1.21, but I used the rounded value of 69.8% given.