The ratio of the amount that Cheng and Amira paid is 1:2 respectively.
The amount earned by Amira when they sell the apartment is $28,000.
The given parameters:
Let the amount paid by Amira = x
The amount paid by Amira is calculated as follows;
[tex]x+ y = 36,000\\\\ x + 12,000 = 36,000\\\\ x = 36,000 - 12,000\\\\ x = 24,000[/tex]
The ratio of the amount each paid is calculated as follows;
[tex]\frac{y}{x} = \frac{12,000}{24,000} = \frac{1}{2} = 1:2[/tex]
The amount earned by Amira when they sell the apartment is calculated as follows;
[tex]x_2 = \frac{2}{1+ 2} \times \$42,000\\\\ x_2 = \frac{2}{3} \times \$42,000 = \ \$28,000[/tex]
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