Question

A cordless telephone will work if it is within 50m of its base, If while you are talking on the phone, you walk 15m away from the base in a southerly direction, then, turn to face west and walk 42m, will the phone still work?

Answer 1

Sketch this out. You will see that is a right triangle problem. Use the Pythagorean theorem:
a^2 + b^2 = c^2
where c is the hypotenuse (long side) of the right triangle. a and b are the other sides.

Answer 2

an antelope, a zebra and an ostrich are entred in a 100metre race. if their top speeds are 95 km/h and 50 kn/h,respectively, caculate how many seconds after the antelope the zebra and the ostrich will complete the race?