Multiplication: One man can eat 3 mangoes. How many mangoes can 5 men eat?
Inverting it into division stories
Division story: There are 15 mangoes, how do you divide it among 5 men.
Division other story: One man can eat 3 mangoes. How many men will eat 15 mangoes.
Its interesting that almost all children in 6th grade have only heard or said the first division story, but can't associate using the other information i.e. how much one man eats with a division story. Much like:
Story: A car covers 60 km in 2 hrs. What is its speed.
Other Story: A car travels at 30 km/hr. How long does it take to cover 60 km.
I find they are too used to multiplication stories being associated with one man, one hr, etc that they are unable to move beyond this experience.
Its also interesting that in younger grades teachers use only one story for subtraction
Story: There are 6 pebbles, if you remove 3 how many are left.
Other story: There are 6 pebbles, I take away some and there are 3 left. How many did I take away?
What is your favorite other story?