# Coffee

Coffee merchant has coffee robusta and arabica species. 1 kg Robusta worth 450 CZK, Arabica 1 kg is 300 CZK more expensive. Calculate how many kilograms of Robusta and Arabica will need to produce 30 kg of the mixture so that the mixture cost is 490 CZK per 1 kg?

Result

r =  26 kg
a =  4 kg

#### Solution:

r+a = 30
450r+(450+300)*a = 30*490

a+r = 30
750a+450r = 14700

a = 4
r = 26

Calculated by our linear equations calculator.

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