42) Each one of 100 boxes is filled with 50 one-rupee coins on the first day and 25 more coins are added every next day. The Arithmetic Progression (AP) representing this situation is
A) 100, 50, 25, 10, …
B) 50, 25, 25, 25, …
C) 50, 75, 100, 125, …
D) 50, 25, 75, 100, …
43) Common difference of the AP 3, 1, -1, -3, … is
A) 1
B) -2
C) -1
D) 2
44) Tenth term of the AP 1, -1, -3, -5, … is
A) -15
B) -17
C) -13
D) -10
45) The sum of the first 22 terms of the AP 8, 3, -2, … is
A) -979
B) 979
C) 1028
D) -1028
View Answer
A) -979
Explanation:a = 8, d = -5 →
Sum = ![\frac{n}{2} [2a + (n - 1)d] = \frac{22}{2} [16 + 21(-5)] = 11(16 - 105) = 11(-89) = -979](https://www.mcqbits.com/wp-content/ql-cache/quicklatex.com-acd3ab42c4e709501bd1ce7e85842bda_l3.png "Rendered by QuickLaTeX.com")
→ -979
46) D and E are the midpoints of sides AB and AC of a triangle ABC respectively and BC = 10 cm. If DE ∥ BC, then the length of DE is
A) 3 cm
B) 5 cm
C) 4 cm
D) 6 cm