150 likes | 309 Views
Simultaneous Equations Diet Balancing. Simultaneous Equations. Used to balance for 2 nutrients Usually protein and energy Balances for required amounts Lb, kg, or Mcal Uses 2 ingredients or 2 mixtures of ingredients. Simultaneous Equations. Identify feeds and their composition
E N D
Simultaneous Equations • Used to balance for 2 nutrients • Usually protein and energy • Balances for required amounts • Lb, kg, or Mcal • Uses 2 ingredients or 2 mixtures of ingredients
Simultaneous Equations • Identify feeds and their composition • Feed A – 10% CP, 80% TDN • Feed B – 35% CP, 50% TDN
Simultaneous Equations • Identify animal requirements • 0.8 lb CP and 4.0 lb TDN per day • Let A = lb of Feed A needed • Let B = lb of Feed B needed
Simultaneous Equations • Equation describing CP • Diet must supply 0.8 lb of CP so • (A x 0.10) + (B x 0.35) = 0.8 lb CP Lb CP reqmt Lb Feed A Lb Feed B CP in Feed A CP in Feed B
Simultaneous Equations • Equation describing TDN • Diet must supply 4.0 lb of TDN so • (A x 0.80) + (B x 0.50) = 4.0 lb TDN Lb TDN reqmt Lb Feed A Lb Feed B TDN in Feed A TDN in Feed B
Simultaneous Equations • 2 equations with the same unknowns • 0.10A + 0.35B = 0.8 lb CP • 0.80A + 0.50B = 4.0 lb TDN
Simultaneous Equations • Multiply 1 equation by a factor that will make one unknown the same in both • 0.10A + 0.35B = 0.8 lb CP • 0.80A + 0.50B = 4.0 lb TDN • 0.80/0.10 = 8, so multiply 1st eq by 8
Simultaneous Equations • 8 (0.10A + 0.35B) = 8 (0.8 lb CP) • 0.8A + 2.8B = 6.4 lb new equation
Simultaneous Equations • Subtract the 2nd eq from new equation • 0.8A + 2.8B = 6.4 lb new equation • 0.8A + 0.5B = 4.0 lb 2nd equation • 0 + 2.3B = 2.4
Simultaneous Equations • Solve for unknown • 0 + 2.3B = 2.4 • B = 2.4/2.3 • B = 1.04 • What was B? • Lb Feed B
Simultaneous Equations • Substitute 1.04 for B in either original eq • 0.10A + 0.35B = 0.8 lb • 0.10A + 0.35(1.04) = 0.8 • 0.10A = 0.8 – 0.364 • 0.10A = 0.436 • A = 0.436/0.10 = 4.36 lb Feed A
Simultaneous Equations • Our diet consists of: • 1.04 lb Feed B • 4.36 lb Feed A
Simultaneous Equations • Check our work: • 1.04 lb Feed B x 0.35 = 0.364 lb CP • 4.36 lb Feed A x 0.10 = 0.436 lb CP • 0.8 lb CP
Simultaneous Equations • Check our work: • 1.04 lb Feed B x 0.50 = 0.52 lb TDN • 4.36 lb Feed A x 0.80 = 3.48 lb TDN • 4.0 lb TDN