Gardener 5

The gardener bought 17 apple trees and 11 pears. He paid a total of €111.65. How many euros did 1 pear cost, if we know that its price was 35 cents higher than the price of 1 apple tree? How much would the gardener pay for 28 apple trees and 15 pears?

Correct answer:

h =  4.2 eur
x =  170.8 eur

Step-by-step explanation:

$$\begin{gathered} 17j+11h=111.65 \\ h=0.35+j \\ 17j+11\cdot (0.35+j)=111.65 \\ 17\cdot j+11\cdot (0.35+j)=111.65 \\ 28j=107.8 \\ j=\frac{107.8}{28}=3.85 \\ j=\frac{77}{20}=3.85 \\ h=0.35+j=0.35+3.85=4.2\text{eur} \end{gathered}$$

$x=28\cdot j+15\cdot h=28\cdot 3.85+15\cdot 4.2=170.8\text{eur}$

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