part (a) =(2+2=4 marks) Testing of certain type of circuit board resulted in a long-run percentage of defectives is 20%. Let X= no. of defective boards in a random sample of size n=10 4- The probability that X4 is; (a) 0.967 (b) 0.879 (c) 0.957 (d) 0.630 5- The expected value and standard deviation of x are; part (a) =(2+2=4 marks) Testing of certain type of circuit board resulted in a long-run percentage of defectives is 20%. Let X= no. of defective boards in a random sample of size n=10 4- The probability that X4 is; (a) 0.967 (b) 0.879 (c) 0.957 (d) 0.630 5- The expected value and standard deviation of x are