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Part (a) - dividing a total quantity given a ratio

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Part (b) - given the value of one part of the ratio to find the total quantity.

", "licence": "None specified"}, "statement": "

The N:P:K content listed on fertiliser labels is the ratio of nitrogen, phosphorus and potassium (in that order) for that particular fertiliser blend. For a given bag of fertiliser with an N:P:K ratio of:

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$\\var{part1}$ : $\\var{part2}$ : $\\var{part3}$

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Part (a)

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Divide the quantity {total}kg into parts according to the ratio

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{part1} : {part2} : {part3}

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Step 1: Find the sum of the parts:

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{part1} + {part2} + {part3} = {part1+part2+part3}

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Step 2: Divide the total quantity by the sum of the parts to find the value of one part.

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$\\frac{\\var{total}}{\\var{s_parts}}$ = {total/(part1+part2+part3)} kg

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Step 3: Multiply the value of one part by the number of parts for each nutrient (N, P and K)

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N:  {total/(part1+part2+part3)} $\\times$ {part1}  = {N_ans_r} kg

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P:  {total/(part1+part2+part3)} $\\times$ {part2}  = {P_ans_r} kg

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K:  {total/(part1+part2+part3)} $\\times$ {part3}  = {K_ans_r} kg

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Part (b)

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Give the size of one part ({nitrogen} g of nitrogen), find the total mass of the nutrients in the fertiliser.

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Step 1: Divide the mass of nitrogen by its number of parts to find the value of one part.

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$\\frac{\\var{nitrogen}}{\\var{part1}}$ = {unit_g} g

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Step 2: Mutiply the value of one part by the sum of the parts to find the total mass of nutrients.

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{unit_g} $\\times$ {s_parts} = {total_g} g

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If the bag contains $\\var{total}$ kg of this nutrient mix, how many kilograms of each nutrient is present? Express your answer to one decimal place.

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N = [[0]] kg

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P = [[1]] kg

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K = [[2]] kg

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If a second bag contains $\\var{nitrogen}$ g of nitrogen, what is the total mass of nutrients (N:P:K) in the fertiliser? Express your answer to the nearest whole number.

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Total mass = [[0]] g

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