An aircraft flew a distance of x km from Amsterdam to Cairo at an average speed of 820 km/h and returned non-stop by the same route at an average speed of 656 km/h. Given that the aircraft took 1 hour more for the return trip, calculate x. A coach took 7/2 hours to travel a distance of 240km from Kuala Lumpur to Cameron Highlands. It travelled part of the journey at an average speed of 60 km/h and the rest of the journey at 75 km/h. Calculate the distance it travelled at 60km/h. The distance from Amy's house to the nearest bus-stop is 240 m. On a particular day, Amy walks towards the bus-stop at an average speed of 30 meters per minute from the instant the leaves her house. After walking for a distance of x m, Amy sees her bus approaching. She then runs towards the bus-stop at an average speed of 150 metres per minute. (a) Finds, in terms of x, an expression for (i) the distance that Amy runs in metres, (ii) the number of minutes that Amy walks, (iii) the number if minutes that Amy runs. (b) Given that the time taken by Amy to reach the bus-stop is 6 minutes, find the value of x. To reach his office on time, Mr Chin usually drives to work at an average speed of 75km/h. However, if Mr Chin increases his average driving speed by 5 km/h, he will reach his office 10 minutes earlier. If the distance Mr Chin needs to travel to reach his office is represented by x km, form an equation in x and solve for x. The follwing diagram shows a rectangular tank and two taps A and B. Tap A alone can fill the tank in 4 hours while tap B alone can fill the tank in 6 hours. taps A and B together can fill the tank in 1 minutes. Form an equaion in t and solve it to find the time, t, in minutes, taps A and B together would take to fill the tank.
Mathematics - 2 Answers
Random Answers, Critics, Comments, Opinions :
1 :
i think the first one will be: x=vt x=820t x=656(t+1) so 820t-656t-656=0 164t=656 t=t h and x=820*4=3280 km
2 :
The follwing diagram shows a rectangular tank and two taps A and B. Tap A alone can fill the tank in 4 hours while tap B alone can fill the tank in 6 hours. taps A and B together can fill the tank in 1 minutes. Form an equaion in t and solve it to find the time, t, in minutes, taps A and B together would take to fill the tank. 1/t = 1/A + 1/B 1/t = 1/4 + 1/6 then solve for t .
