Exams

Let P's speed = x km/hr. Then, Q's speed = (7 - x) km/ hr.

So, 24/x + 24/(7 - x) = 14

x2 - 98x + 168 = 0

(x - 3)(x - 4) = 0 => x = 3 or 4.

Since, P is faster than Q,

so P's speed = 4 km/hr and Q's speed = 3 km/hr.

No. of  sweets each student get = 20% of 65 = 13

No. of sweets each teacher get = 40% of 65 = 26

No. of sweets distributed to 65 students =  13 × 65 = 845

No. of sweets distributed to 4 teachers = 4 × 26 = 104

Therefore, the total no. of sweets there = 845 + 104 = 949.

In this type of question, we will first calculate the distance covered in given time.

Distance covered will be : Number of revolutions x Circumference 

So we will be having distance and time, from which we can calculate the speed. 

Radius of wheel = 70 / 2 = 35 cm

Distance covered in 40 revolutions will be 40*circumferene=40*2πr=40*2*227*35=8800cm = 88 m

Distance covered in 1 sec  = 8810=8.8m/s=8.8*185km/hr=31.68km/hr

Choose 1 person for the single room & from the remaining choose 2 for the double room & from the remaining choose 4 people for the four person room, 

 Then, ⁷C₁ x ⁶C₂ x ⁴C₄ 

_{= 7 x 15 x 1 = 105}

Let the original price of the cycle be 100. After the first reduction the price will be 75.

This new price is then reduced by 20% = 0.8 x 75 = 60

60 represents a reduction of 40 percent on the original.

By mistake = x/10 

Actual value = x * 10 

% Change = 10x-x1010x×100 = 99100×100  = 99% (negative)

Since actual value is greater than the wrong value.