Question 648Navigation General70% to pass
The chart indicates the variation was 3°45'W in 1988, and the annual change is decreasing 6'. If you use the chart in 1991 how much variation should you apply?
AI Explanation
The correct answer is A) 3°27'W.
To arrive at this answer, we need to calculate the variation in 1991 based on the given information:
- The variation was 3°45'W in 1988
- The annual change is decreasing by 6'
- The question asks for the variation in 1991, which is 3 years after 1988
To find the variation in 1991, we need to subtract the change in variation over the 3-year period from the 1988 value. The change in variation is 3 years x 6' per year = 18', which is 0°18'. Subtracting this from the 1988 value of 3°45'W gives us the 1991 variation of 3°27'W.
The other answer choices are incorrect because they do not properly account for the decreasing annual change in variation. Option B is incorrect because it assumes the variation is eastward, option C assumes the variation increased, and option D also assumes an eastward variation.
Related Questions
#646 Compass error is equal to the _______________.#647 When changing from a compass course to a true course you should apply _______________.#649 The chart indicates the variation was 3°45'W in 1988, and the annual change is increasing 6'. If you use the chart in 1991 how much variation should you apply? #650 The chart indicates the variation was 3°45'E in 1988, and the annual change is increasing 6'. If you use the chart in 1991 how much variation should you apply? #651 Variation is a compass error that you _______________.