Question

Lara makes birdseed by mixing peanuts and sunflower seeds in a 2:3 ratio. The peanuts costs 3p per 10g and the sunflower seeds cost 9p per 10g. Lara sells the birdseed £1 per 100g portion.

How much profit does Lara make on each portion? Give your answer in pence.
Step by step explanation plssss tqsm. ​

Answer 1

Lara will do a profit of 34 pence by 100 grams of birdseed.

Explanation:

The given ratio means that there are 2 grams of peanuts and 3 grams of sunflower per each 5 grams of birdseed. Now, we obtain the amount required of peanuts and sunflower for 100 grams of birdseed by simple rule of three:

Peanuts

`x = (100\,g)/(5\,g)* 2\,g`

`x = 40\,g`

Sunflower

`y = (100\,g)/(5\,g)* 3\,g`

`y = 60\,g`

If we know that 10 grams of sunflower cost 9 pence and 10 grams of sunflower cost 3 pence, then the total cost of production of 100 grams portion:

`C = \left((0.03\,GBP)/(10\,g) \right)\cdot (40\,g)+\left((0.09\,GBP)/(10\,g) \right)\cdot (60\,g)`

`C = 0.66\,GBP`

And the profit done by Lara is:

`\Delta C = 1\,GBP - 0.66\,GBP`

`\Delta C = 0.34\,GBP`

Lara will do a profit of 34 pence by 100 grams of birdseed.