Quantitative Aptitude - Arithmetic Ability Questions

In the following question, four number pairs are given. The number on left side of (–) is related to the number on the right side of (–) with some Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

Find co-ordinates of the mid point of the segment joining points C (3,-5) and D (-7,3).

If the shopkeeper sells an item at Rs 4400 which is marked as Rs 5000, then what is the discount that he is offering?

Which single discount will be equal to two successive discounts of 12% and 5%?

What is the area (in sq cm) of a rectangle if its diagonal is 25 cm and one of its sides is 24 cm?

Triangle DEF is right angled at E. If cot D = 5/12, then what is the value of sin F?

The slopes of two lines are 1 and √3. What is the angle between these two lines?

The sum of a fraction and 3 times its reciprocal is 37/10. What is the fraction?