there must be one more choice: 145
a- b- c, from first 2 sets we can assume that c=2a-b
5-7-3 2 * 5 - 7 = 3 20-30-10 2 * 20 - 30 = 10 95-45- 2 * 95 - 45 = 145
86 is the correct answer
What would be the value of ? in the following grid -
5 7 3 20 10 30 95 45 ?
On behalf of Sture Sjöstedt
