Find the mean proportion of: 8.1 and 2.5

Sum

Let the x be the mean proportion of 8.1 and 2.5
∴ 8.1 : x : : x : 2.5
∴ x2 = 8.1 x 2.5
∴ x = `sqrt(8.1 xx 2.5)`
= `sqrt(20.25)`
= 4.5.

shaalaa.com

Is there an error in this question or solution?

Chapter 6 Ratio and Proportion
Exercise 7.2 | Q 4.3

Find the third proportional to `x/y + y/x` and `sqrt(x^2 + y^2)`

If a : b = c : d, show that (a - c) b² : (b - d) cd = (a² - b² - ab) : (c² - d² - cd).

Find the value of x in the following proportions : 2.5 : 1.5 = x : 3

Find the fourth proportional to 1.5, 2.5, 4.5

Write (T) for true and (F) for false in case of the following:

81 kg : 45 kg : : 18 men : 10 men

The weight of 65 books is 13 kg.
(i) What is the weight of 80 such books?
(ii) How many such books weigh 6.4 kg?

If a, b, c are in proportion, then

10 books is to 15 books as 3 books is to 15 books

Sleeping time of a python in a 24 hour clock is represented by the shaded portion in the following figure.

The ratio of sleeping time to awaking time is ______.

If `(a + b)^3/(a - b)^3 = 64/27`