Two times a number and three times another number makes 120. Three times the second number when subtracted from four times the first number gives 78. Find the numbers.​

Answer :

Answer:

Let's denote the two unknown numbers as \( x \) and \( y \).

According to the problem, we have two equations:

1. Two times the first number and three times the second number makes 120:

\[

2x + 3y = 120

\]

2. Three times the second number subtracted from four times the first number gives 78:

\[

4x - 3y = 78

\]

To find the values of \( x \) and \( y \), we will solve these two simultaneous linear equations.

First, we add the two equations to eliminate \( y \):

\[

2x + 3y = 120 \quad \text{(Equation 1)}

\]

\[

4x - 3y = 78 \quad \text{(Equation 2)}

\]

Adding these equations:

\[

(2x + 3y) + (4x - 3y) = 120 + 78

\]

\[

2x + 4x + 3y - 3y = 198

\]

\[

6x = 198

\]

\[

x = \frac{198}{6}

\]

\[

x = 33

\]

Now, substitute \( x = 33 \) back into one of the original equations to solve for \( y \). We use Equation 1:

\[

2x + 3y = 120

\]

\[

2(33) + 3y = 120

\]

\[

66 + 3y = 120

\]

\[

3y = 120 - 66

\]

\[

3y = 54

\]

\[

y = \frac{54}{3}

\]

\[

y = 18

\]

Thus, the two numbers are:

\[

x = 33

\]

\[

y = 18

\]

### Verification:

- For the first equation: \( 2x + 3y = 2(33) + 3(18) = 66 + 54 = 120 \), which is correct.

- For the second equation: \( 4x - 3y = 4(33) - 3(18) = 132 - 54 = 78 \), which is also correct.

So, the numbers are:

\[

\boxed{33 \text{ and } 18}

\]

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