Working out (-2) * (-3) * (-4), a learner pairs the opening two negative factors, drops the sign of the third and answers 24. What is the correct value?

Explication

Pairing the opening two negative factors does give six, but that six still has to be multiplied by a factor below zero, which flips the running result once more and leaves it twenty-four units below zero. The learner stops one flip early; stopping even sooner reports the six itself, and adding the three factors rather than multiplying them lands somewhere else again.