Question 3 : A survey conducted for 50 members of staff of Cadbury plc shows that 30 of them have degree while 35 possess H.N.D. if 8 of the employees possess neither of the certificate how many have both degree and H.N.D 23 16 24 18
50-8=42. So 42 have something
Let B be the number with both
Degree only = 30-B
HND only = 35-B
so
30-B + 35-B +B = 42
65-B=42
B=23
Or you could have gone backwards and just checked the answers. :)
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