The weight of 2 bags of almonds and 7 bags of peanuts is 760g, while the weight of 4 bags of almonds and 5 bags of peanuts is 980g. How many grams does each bag of almonds and each bag of peanuts weigh?



Answer :

Let's denote the weight of one bag of almonds as [tex]\( A \)[/tex] grams and the weight of one bag of peanuts as [tex]\( P \)[/tex] grams.

We are provided with two key pieces of information that lead to the following system of equations:

1. [tex]\( 2A + 7P = 760 \)[/tex]
2. [tex]\( 4A + 5P = 980 \)[/tex]

We need to solve this system of equations to find the values of [tex]\( A \)[/tex] and [tex]\( P \)[/tex].

### Solving Step-by-Step

1. Equation Setup:
- First equation: [tex]\( 2A + 7P = 760 \)[/tex]
- Second equation: [tex]\( 4A + 5P = 980 \)[/tex]

2. Express one variable in terms of the other:
Let's solve the first equation for [tex]\( A \)[/tex]:

[tex]\[ 2A + 7P = 760 \implies A = \frac{760 - 7P}{2} \][/tex]

3. Substitute into the second equation:
Substitute [tex]\( A \)[/tex] from the first equation into the second equation:

[tex]\[ 4\left(\frac{760 - 7P}{2}\right) + 5P = 980 \][/tex]

4. Simplify the equation:
First, simplify the left-hand side:

[tex]\[ 4 \times \frac{760 - 7P}{2} = 2(760 - 7P) = 1520 - 14P \][/tex]

Thus the equation becomes:

[tex]\[ 1520 - 14P + 5P = 980 \][/tex]

Simplifying further:

[tex]\[ 1520 - 9P = 980 \][/tex]

5. Solve for [tex]\( P \)[/tex]:
[tex]\[ 1520 - 980 = 9P \][/tex]
[tex]\[ 540 = 9P \][/tex]
[tex]\[ P = \frac{540}{9} = 60 \][/tex]

So, the weight of one bag of peanuts, [tex]\( P \)[/tex], is 60 grams.

6. Substitute [tex]\( P \)[/tex] back into the first equation to find [tex]\( A \)[/tex]:
[tex]\[ 2A + 7(60) = 760 \][/tex]
[tex]\[ 2A + 420 = 760 \][/tex]
[tex]\[ 2A = 760 - 420 \][/tex]
[tex]\[ 2A = 340 \][/tex]
[tex]\[ A = \frac{340}{2} = 170 \][/tex]

So, the weight of one bag of almonds, [tex]\( A \)[/tex], is 170 grams.

### Conclusion

Each bag of almonds weighs 170 grams, and each bag of peanuts weighs 60 grams.