If a car runs at a constant speed and takes 4.5 hrs to ru...
If a car runs at a constant speed and takes 4.5 hrs to run a distance of 225 km, what time will it take to run 150 km?
2 hrs
4 hrs
3 hrs3 hrs
1 hr
Correct answer is C
Let T be the time taken and D is the distance
For the case given in the problem, the distance covered is directly proportional to the time taken i.e D α T
⇒ D = ST where S is the constant speed
D = 225 km and T = 4.5 hrs
∴ 225 = S x 4.5
S = \(\frac {225}{4.5}\) = 50km/hr
When D = 150km
D = ST
150 = 50 \(\times\) T
T = \(\frac {150}{50}\) = 3 hrs
So it will take 3 hrs
Factorize completely; (4x+3y)\(^2\) - (3x-2y)\(^2\) ...
Simplify 3 - 2 \(\div\) \(\frac{4}{5}\) + \(\frac{1}{2}\)...
Write as a single fraction: \(\frac{5}{6r} - \frac{3}{4r}\)...
A man sells his new brand car for N420,000 at a gain of 15%. What did it cost him? ...
At what value of X does the function y = -3 - 2x + X2 attain a minimum value? ...