# How much per KG

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### How much per KG

2KG Trout & 3kg cod = \$144 3kg Trout & 2kg cod = \$156

How much per kg for each type of fish?

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brown.ds

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### Re: How much per KG

2KG Trout & 3kg cod = \$144 3kg Trout & 2kg cod = \$156

2*trout + 3*cod = 144 <=> trout = (144 - 3cod)/2

3*trout + 2*cod= 156
3(144 - 3cod)/2 + 2cod = 156
3(144 - 3cod) + 4cod = 156*2
432 - 9cod+4cod = 312
-5cod = -120
cod = $24 per kg trout = (144 - 3cod)/2 Math Tutor Site Admin Posts: 396 Joined: Sun Oct 09, 2005 11:37 am Reputation: 21 ### Re: How much per KG 2KG Trout & 3kg cod = \$144 ---- 1st equation
3kg Trout & 2kg cod = \$156 ------2nd equation By solving 1st equation, we will get 2*trout + 3*cod = 144 <=> trout = (144 - 3cod)/2 -----3rd equation Put this value of trout from equation 3rd into 2nd equation, we get 3*trout + 2*cod= 156 3(144 - 3cod)/2 + 2cod = 156 3(144 - 3cod) + 4cod = 156*2 432 - 9cod+4cod = 312 -5cod = -120 cod = \$24 per kg

So, the Cod is \$24 per kg and now we will put this value into 2nd equation 3*trout + 2*24= 156 3t + 48 =156 3t = 156 - 48 3t = 108 t= 108/3 t= 36 So we find the value of trout = \$36 per kg

Trout = \$36 per kg & Cod = \$24 per kg

leesajohnson

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### Re: How much per KG

Let T = cost per kg of Cod and T = Cost per kg of Trout
2T + 3C = 144
3T + 2C = 156
T - C = 12 --> T = 12 + C

24 + 2C + 3C = 144

5C = 120
C = 24
T = 36

So Cod is \$24 per Kg and Trout is \$36 per Kg
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