In a survey of teenagers, 2/3 responded that they got regular exercise, and 4/5 of those said that walking was their main form of exercise. What fraction of the teenagers mainly exercise by walking?(1 point)
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To find the fraction of teenagers that mainly exercise by walking, we need to multiply the fractions from the survey.
Fraction that got regular exercise = 2/3
Fraction of those who got regular exercise that mainly walk = 4/5
Multiplying these fractions, we get:
(2/3) * (4/5) = 8/15
Therefore, the fraction of teenagers that mainly exercise by walking is 8/15. Answer: \boxed{\frac{8}{15}}.