Answer:
The pounds of roasted pistachios nuts Christopher purchases is 10 pounds
Explanation:
The given parameters are;
The price of raw almonds at Nuts.com = $8 per pound
The price of roasted pistachios at Nuts.com = $9 per pound
The amount Christopher spends on Nuts = $162
The quantity of nuts Christopher purchase = 19 pounds
Let the pounds of raw almonds nuts Christopher purchases = X and the pounds of roasted pistachios nuts Christopher purchases = Y
∴ $8·X + $9·Y = $162...(1)
X + Y = 19...(2)
Making X the subject of the formula in equation (2), we have;
X = 19 - Y
Substituting the value X in equation (1) gives;
$8·(19 - Y) + $9·Y = $162
$152 - $8·Y + $9·Y = $162
$1·Y = $162 - $152 = $10
Y = $10/($1) = 10
Y = 10 pounds
The pounds of roasted pistachios nuts Christopher purchased = Y = 10
The pounds of roasted pistachios nuts Christopher purchases = 10 pounds
X = 19 - Y = 19 - 10 = 9
X = 9 pounds
The pounds of raw almonds nuts Christopher purchases = X = 9
The pounds of raw almonds nuts Christopher purchases = 9 pounds