If a person burns 2171 cal each day, how much energy (kj) does she burn in 2 days?

She will burn 18.17 KJ of energy in 2 days.

Energy can be measured in both joules and calories. The following units of energy are converted as follows:

1 calorie = 4.184 Joules

2171 calories = (2171 × 4.184) joules

= 9083.464 Joules

Since 1 kilojoules = 1000 joules

9083.464 Joules = (9083.464/1000) KJ

= 9.083 KJ

This means that the person burns 9.083 KJ of energy per day.

Hence, in 2days, the person will burn;

2 × 9.083 KJ

= 18.17 KJ of energy.

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