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Aptitude: Problems on H.C.F and L.C.M

problem on H.C.F and L.C.M    1. Factors and Multiples: –If number a divided another number b exactly, we say that a is a factor of b. In this case, b is called a multiple of a. 2. Highest Common Factor (H.C.F.) or Greatest Common Measure (G.C.M.) or Greatest Common …

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Aptitude: Problems on Numbers

FORMULA a + b)(a – b) = (a2 – b2)  (a + b)2 = (a2 + b2 + 2ab)  (a – b)2 = (a2 + b2 – 2ab)  (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ca) (a3 + b3) = (a …

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Aptitude: Numbers

  Some Basic Formula i. (a + b)(a – b) = (a2 – b2) ii. (a + b)2 = (a2 + b2 + 2ab) iii. (a – b)2 = (a2 + b2 – 2ab) iv. (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc …

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Aptitude :: Compound Interest

Let Principal = P, Rate = R% per annum, Time = n When interest is compound Annually:    Amount = P 1 + R n 100 When interest is compounded Half-yearly:     Amount = P 1 + (R/2) 2n 100 When interest is compounded Quarterly:     Amount = P …

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APTITUDE-TIME AND WORKS

The money  borrowed or lent out for a certain period is called the principal or the sum. Interest: Extra money paid for using other’s money is called interest. Simple Interest (S.I.): If the interest on a sum borrowed for certain period is reckoned uniformly, then it is called simple interest. Let Principal = P, Rate …

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aptitude :: height and distance

Trigonometry: In a right angled OAB, where BOA = , i. sin = Perpendicular = AB ; Hypotenuse OB ii. cos = Base = OA ; Hypotenuse OB iii. tan = Perpendicular = AB ; Base OA iv. cosec = 1 = OB ; sin AB v. sec = 1 …

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TIME AND DISTENCE

TIME AND DISTENCE FORMULA 1. Speed, Time and Distance: Speed = Distance , Time = Distance , Distance = (Speed x Time). Time Speed 2. km/hr to m/sec conversion: x km/hr = x x 5 m/sec. 18 3. m/sec to km/hr conversion: x m/sec = x x 18 km/hr. 5 …

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Problems on Trains

Problems on Trains (Formula) 1. km/hr to m/s conversion: a km/hr =a * 5/18 m/s. 2. m/s to km/hr conversion: a m/s =a * 18/5 km/hr. 3. Formulas for finding Speed, Time and Distance 4. Time taken by a train of length l metres to pass a pole or standing …

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