Three fifths of the members of a hiking club went on the last hiking trip. if 39 people went on the trip, how many are in the club

Ammonia molecules have three hydrogen atoms and one nitrogen atom.how many of each atom arein five molecules of ammonia

Present age of man is 45 years, 5 years back his age was 4 times age of his son what is present age of his son?

The area (a) of a circle with a radius of r is given by the formula and its diameter (d) is given by d=2r. arrange the equations in the correct sequence to rewrite the formula for diameter in terms of the area of the circle.