The next number of the sequence 1/2, 3/4, 5/8, 7/16 ………is: (1) 10/24 (2) 11/32 (3) 9/24 (4) 9/32
Solution: Sequence of numerators ⇒1,3,5,7,9 Sequence of denominators ⇒2,4,8,16,32 :. Next fraction = 9/32 Then the option is (4) 9/32
What is the area of the triangle whose sides are 9cm, 10cm and 11cm?
(1) 30cm2 (2) 60cm2 (3) 30√2cm2 (4) 60√2cm2 Solution: Semi-perimeter, s=9+10+11/2 = 15cm Area of triangle = √s(s-a)(s-b)(s-c) =√15(15-9)(15-10)(15-11) =√15*6*5*4 = 30√2cm2 Then the option is (3) 30√2cm2
What is the area of the triangle whose sides are 9cm, 10cm and 11cm? Read More »
If 4b2+1/b2 = 2, then the value of 8b3+1/b3 is :
(1) 0 (2) 1 (3) 2 (4) 5 Solution: (2b+1/b)2 = 4b2+1/b2+2*2b*1/b =2 + 4 = 6 ⇒ 2b+1/b =√6 .’. 8b3+1/b3 = (2b+1/b)3 -3*2b*1/b(2b+1/b) = (√6)3 -6(√6) = 6(√6) – 6(√6) =0 Then the option is (1)
If 4b2+1/b2 = 2, then the value of 8b3+1/b3 is : Read More »
A company produces an average of 4000 items per month for the first 3 months. How much items, it must produce on an average per month over the next 9 months to average 4375 items per month over the whole year?
(1) 4500 (2) 4600 (3) 4680 (4) 4710 Solution: Let average production of a company in 9 months be x items :. Accordingto question, 4375 = 3*4000*+9*x/12 or, 4375*12= 12*1000+ 9*x :. 9*x = 12 (4375- 1000) = 12*3375 :. x =12*3375/9 = 4500 Then the option is (1) 4500
If 0∘ < θ < 90∘, and tan2θ-(√3+1) tan θ+√3=0, then θ=?
(1)30∘ (2) 45∘ (3) 60∘ (4) 45∘ or 60∘ Solution: tan2θ- √3 tan θ -tan θ +√3=0 = tan θ (tan θ -√3) -1(tan θ -√3) =0 = (tan θ -1) (tan θ -√3)=0 = tan θ =1=tan 45∘ = θ = 45∘ Again, tan θ -√3 =0 ⇒ tan θ =√3 = tan 60∘ ⇒ θ = 60∘
If 0∘ < θ < 90∘, and tan2θ-(√3+1) tan θ+√3=0, then θ=? Read More »
In a cricket match the total number of runs scored by Sachin, Vinod and Sourav is 285. The ratio of the number of runs scored by Sachin and Sourav is 3 : 2 and that of the runs scored by Sourav and Vinod is also 3 : 2. The number of runs scored by Sachin in that match is
(1) 135 (2) 90 (3) 60 (4) 140 Solution: Sachin : Sourav = 3 : 2 Sourav : Vinod = 3 : 2 Ratio of the runs scored by Sachin, Sourav and Vinod respectively = 3*3 : 2*3 : 2*2 = 9: 6: 4 ;. Runs scored by Sachin = 9/19*285=135 Then the option is
At present, the ratio of the age of Maya and Chhaya is 6 : 5 and fifteen years from now, the ratio will get changed to 9 : 8. Maya’s present age is:
(1) 21 years (2) 24 years (3) 30years (4) 40 years Solution: Let Maya’s present age be 6x years and Chhaya’s present age be 5x years. After 15 years, 6x+15/5x+15 = 9/8 ⇒ 48x + 120 = 45x + 135 ⇒ 48x – 45x = 135 – 120 ⇒ 3x= 15 ⇒ x=5 :. Maya’s present age =
Two men start together to walk a certain distance, one at 4 km/h and another at 3 km/h.The former arrives half an hour before the latter. Find the distance.
(1) 8km (2)7km (3) 6 km (4)9km Solution: If the required distance be x km,then x/3-x/4=1/2 ⇒ 4x-3x/12=1/2 ⇒ x/12=1/2 ⇒ x= 6km Then the option is (3) 6km
If 5√x+12√x=13√x, then x is equal to :
(1) 25/4 (2) 4 (3)9 (4) 16 Solution: 5√x+12√x=13√x We know that 52+122=132 [PythagoreanTriplet) :. √x =2 ⇒ x = 22 =4 Then the option is (2) 4
If 5√x+12√x=13√x, then x is equal to : Read More »
The missing number in the sequence 5,6,15,…?…. 89,170,291 is:
(1) 50 (2) 40 (3) 42 (4) 32 Solution: The pattern of the given number series is : 5 + 12 = 6 6 + 32 = 15 15 +52= 40 40+72= 89 89+92= 170 Then the missing number is 40.
The missing number in the sequence 5,6,15,…?…. 89,170,291 is: Read More »