Find the third proportional to Rs. 3, Rs. 12

Sum

Let x be the third proportional to Rs. 3 and Rs. 12
then Rs. 3 : Rs. 12 : : Rs. 12 : x
∴ x = `(12 xx 12)/(3)`
= 48
∴ Third proportional = Rs. 48.

shaalaa.com

Is there an error in this question or solution?

Chapter 6: Ratio and Proportion - Exercise 7.2

Chapter 6 Ratio and Proportion
Exercise 7.2 | Q 3.3

If a, b, c are in continued proportion and a(b - c) = 2b, prove that `a - c = (2(a + b))/a`

If p + r = mq and `1/q + 1/s = m/r`; then prove that p : q = r : s.

Check whether the following numbers are in continued proportion.

1, 2, 3

Find the third proportional to `5(1)/(4) and 7.`

Verify the following:

39 : 65 : : 141 : 235

If `x/a = y/b = z/c`, prove that `[(a^2x^2 + b^2y^2 + c^2z^2)/(a^2x + b^3y +c^3z)]^3 = "xyz"/"abc"`

If ax = by = cz; prove that `x^2/"yz" + y^2/"zx" + z^2/"xy" = "bc"/a^2 + "ca"/b^2 + "ab"/c^2`

What number must be added to each of the numbers 15, 17, 34 and 38 to make them proportional?

Find two numbers whose mean proportional is 16 and the third proportional is 128.

Find whether 12, 24, 18, 36 are in order that can be expressed as two ratios that are in proportion