22. 1 Ar. Of = = Ar. Of 1 = so, Ar. Of qua. ABCD = Ans. 1 23. Since, the Circumference of the circle = 88 cm 1 or, 2 So, Ar. of the required sector = 1 = 1 = 77 24. Vol. Of Glass (Shaped frustum of a cone) = 1 = 1 = 1 =102.67 SECTION - D 25. 1 or, = 1 or, = 1 or, or, or, 1 or, Ans. Or Let the usual speed of the plane be x km/hr. 1 Then, By question, or, 1 or, ( 1 Or, 1 Hence, the usual speed of the plane is 750 km/hr. Ans. 26. Required nos. are 252,255, 258, ……..999 1 Here, a + (n-1)d=999 1 or, 252 + (n-1)3=999 1 So, Required sum = sn = Ans. 1 27. Let the nth term of the given AP be the first negative term. 1 Then an < 0 or, a +(n-1)d<0 1 or, 20 +(n-1) (- or, 83 -3n <0 1 or, 3n > 83 or, n > or, n > 1 n 28 Thus, 28th term of the given sequence is the first negative term. Ans.
22. Ar. Of = = 1 Ar. Of = 1 so, Ar. Of qua. ABCD = Ans. 1 23. Since, the Circumference of the circle = 88 cm or, 2 1 So, Ar. of the required sector = 1 = = 77 1 24. Vol. Of Glass (Shaped frustum of a cone) = 1 = 1 = =102.67 1 SECTION - D 25. 1 or, = 1 or, = or, or, 1 or, or, Ans. 1 Or Let the usual speed of the plane be x km/hr. Then, By question, 1 or, 1 or, ( 1 Or, Hence, the usual speed of the plane is 750 km/hr. Ans. 1 26. Required nos. are 252,255, 258, ……..999 1 Here, a + (n-1)d=999 1 or, 252 + (n-1)3=999 1 So, Required sum = sn = Ans. 1 27. Let the nth term of the given AP be the first negative term. Then an < 0 1 or, a +(n-1)d<0 or, 20 +(n-1) (- 1 or, 83 -3n <0 or, 3n > 83 or, n > 1 or, n > n 28 Thus, 28th term of the given sequence is the first negative term. Ans. 1
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