30 less than 10 is 30 - 10 which is -20
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Answer: 7.5 feet
Step-by-step explanation: 12/40*25
B
Step-by-step explanation:
it is the only one that has angles that are right next to eachother!
Let
x = pounds of peanuts
y = pounds of cashews
z = pounds of Brazil nuts.
The total pounds is 50, therefore
x + y + z = 50 (1)
The total cost is $6.60 per pound for 50 pounds of mixture.
The total is equal to the sum of the costs of the different nuts.
Because the cost for peanuts, cashews, and Brazil nuts are $3, $10, and $9 respectively, therefore
3x + 10y + 9z = 50*6.8
3x + 10y + 9z = 340 (2)
There are 10 fewer pounds of cashews than peanuts, therefore
x = y + 10 (3)
Substitute (3) into (1) and (2).
y + 10 + y + z = 50
2y + z = 40 (4)
3(y + 10) + 10y + 9z = 340
13y + 9z = 310 (5)
From (4),
z = 40 - 2y (6)
Substitute (6) into (5).
13y + 9(40 - 2y) = 310
-5y = -50
y = 10
z = 40 - 2y = 40 - 20 = 20
x = y + 10 = 20
Answer:
Peanuts: 20 pounds
Cashews: 10 pounds
Brazil nuts: 20 pounds