What is the fourth proportional to 7, 15 and 21?
Answer & explanation
Correct answer: option 4
Using the direct formula,
Fourth proportion of a, b and c = \(\frac{b\; \times\; c}{a}\)
Fourth proportion = \(\frac{15\; \times\; 21}{7}\)
= 45
What is the fourth proportional to 7, 15 and 21?
Correct answer: option 4
Using the direct formula,
Fourth proportion of a, b and c = \(\frac{b\; \times\; c}{a}\)
Fourth proportion = \(\frac{15\; \times\; 21}{7}\)
= 45