One of the keys on a calculator is faulty. When you press it you get a different number. Some of the results produced by the calculator are shown below. Which is the faulty key?
677Topics: Starter  Arithmetic  Calculator  Problem Solving
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Previous Day  This starter is for 11 February  Next Day
The faulty key is 7
It produces a 2
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If you think faulty calculators still have a use try this.