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Rates, SM-Bank 084 MC

The nutritional information on a power bar is shown below.

 

 
Sandra expends 900 kJ of energy by running for 20 minutes.

If she consumes 100 grams of the power bar, approximately how long should she run to use up the energy it provides?
 

  1. 20 minutes
  2. 30 minutes
  3. 40 minutes
  4. 55 minutes
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\(C\)

Show Worked Solution

\(100\ \text{grams of power bar}\rightarrow 1810\ \text{kJ}\)

\(\text{Exercise required}\) \(=\dfrac{1810}{900}\times 20\)
  \(\approx 2\times 20\)
  \(\approx 40\ \text{minutes}\)

 
\(\Rightarrow C\)