$54 (if 10 for each of the 3 students and 4 dollars each of the 6 students)
$14 if not
2.56 minutes
6 meters a minute÷ 15.36 meters =?
Answer: Heater -Rs 2400; Fan- Rs 1600
Step-by-step explanation:
Given
Ajay bought a fan and a heater for Rs 4000
Suppose the price of fan is x and that of heater is 4000-x
Profit on the fan is 
Loss on heater is 
Total profit is 7% i.e. 

Thus, the price of heater is 
Price of fan is 
Price of heater is 
If the number begins by being rational, multiplying by 0.5 will not change whether or not it is rational. It will remain rational.
That would include any even number 12 * 0.5 = 6
12 started out as rational, so the answer is rational (6)
Any odd number is also rational
23 * 0.5 = 11.5
23 and 11.5 are both rational.
3.636363636 ... is rational so when multiplied by 0.5 the result will be rational.
1.818181818....
So if we start with something irrational like pi
then pi * 0.5 is not rational.
If you have choices, please list them.