Question
The average of a, b and c is 8 less than d. If the
average of a, b, c and d is 42, and the average of b and c is 43. then find the average of (a-6) and (d+2).Solution
ATQ, (a+b+c)/3 = d-8 a+b+c = 3d-24 a+b+c+d=42×4=168 3d-24+d = 168 4d=168+24 ∴ d=192/4 d =48 and again, b+c = 2 × 43 b+c = 86 a + b + c = 3d-24 = 144-24 =120 a = 120-86 = 34 average of (a-6) and (d+2) = ½ [(68-6) + (48+2)] = 112/2 = 5 6
If tanθ = x then find the value of cos 2θ?
sin2 7 ° + sin2 8 ° + sin2 9 ° + sin2 10 ° + ……… + sin2 83 ° = ?
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sin2 7Ëš + sin2 9Ëš + sin2 11Ëš + sin2 12Ëš + ……… + sin2 83Ëš = ?
What is the value of [(sin x + sin y) (sin x – sin y)]/[(cosx + cosy) (cosy – cosx)]?
The value of (3tan10°-tan³10°)/(1-3tan²10°) is equal to
If 2x = cosec @ and 4/x = cot @ then the value of 2(x ² - 1/x ² ) is
If cosec (2A + B) = 2 and cosec (A + B) = 1, find the value of (3A – B).
tan 1˚ × tan 2˚× …………………….tan 88˚ × tan 89˚ = ?
If (sinθ+cosθ)/(sinθ-cosθ) = 2, then the value of sin4 θ is
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