Solution
The 1st term = -3
15th term = 53
15th term = a + d(n-1)
53 = -3 + d(15- 1) [Here n = 15)
53 + 3 = d(14)
14d = 56
d = 4
The common difference is 4.
The smaller the value of the least increment, the more precise a number is.
Length measured to the nearest 1/8 inch will be more precisely specified than length measured to the nearest 1/4 inch.
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In general, precision has little to do with accuracy—how close the measured value is to the actual value. A measurement can be very precise, but just plain wrong. (Many electronic instruments have resolution (precision) that exceeds their accuracy. That is, one or two (or more) of the least-significant displayed digits may be in error.)
