Find z, given the following. (Give your answer correct to two decimal places.)

x = 56, ì = 45 and ó = 5.3
z = 56-45/5.3=47.509=47.51
Find z, given the following. (Give your answer correct to two decimal places.)
x = 245, ì = 223 and ó = 12.4
245-223/12.4=227.02 x-mean/sd=???This is what I used and they are wrong can someone help me?

you close but

z = (x- mu)/sigma

z = (56-45)/5.3 = 2.08

z = 11/5.3 = 2.08

z = (x-mu)/sigma

z = (245-223)/12.4

z = 22/12.4 = 1.77