In a survey of teenagers, 2/3 repsonded that they got regular exercise and 4/5 of those said that walking was their main form of exercising. What fraction of the teenagers mainly exercise by walking?
To find the fraction of teenagers who mainly exercise by walking, we need to multiply the fractions 2/3 and 4/5:
2/3 * 4/5 = (2 * 4) / (3 * 5) = 8/15
Therefore, 8/15 of the teenagers surveyed mainly exercise by walking.