Question

The product of four numbers is 540. Three of the numbers are 2,5 and 9 .find the other number

Answer 1

Let's denote the four numbers as \( a, b, c, \) and \( d \). Given that three of the numbers are \( 2, 5, \) and \( 9 \), we can express this as:

\[
a = 2, \quad b = 5, \quad c = 9
\]

We know the product of all four numbers is:

\[
a \times b \times c \times d = 540
\]

Substituting the known values into the equation gives us:

\[
2 \times 5 \times 9 \times d = 540
\]

First, calculate the product of \( 2, 5, \) and \( 9 \):

\[
2 \times 5 = 10
\]
\[
10 \times 9 = 90
\]

Now we have:

\[
90 \times d = 540
\]

To find \( d \), we divide both sides by \( 90 \):

\[
d = \frac{540}{90}
\]

Calculating that gives:

\[
d = 6
\]

Thus, the fourth number is \( \boxed{6} \).