X - Columbian coffee ( in pounds),
y - Brazilian coffee ( in pounds );
x + y = 100
8.85 x + 3.85 y = 6.55 ( x + y )
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x = 100 - y
8.85 ( 100 - y ) + 3.85 y = 6.55 * 100
855 - 8.55 y + 3.85 y = 655
- 5 y = - 230
y = ( - 230 ) : ( - 5 )
y = 46
x = 100 - 46
x = 54
Answer: 54 pounds of Columbian coffee and 46 pounds of Brazilian coffee should be used.
Answer:
Length = 90 inch.
width = 30 inch
Let width of the rectangle = x inch.
So the length = 3x inch.
Perimeter = 2(length + width) = 2 (3x + x) = 8x.
So,
length = 3x = 3(30) = 90 inch.
width = x = 30 inch