Sam is eating a big hamburger. the first bite was 20% of the hamburger, the second bite was 20% of what is left and so every next bite is 20% of what is left. a how much did the hamburger weigh originally, if after the second bite there was 160g of it left?

The weight of the hamburger is 160g after two bites.

Each bite takes away 20% of the weight of the burger, so we'll divide the initial weight by a percentage to find the weight before the bite.

The starting weight is 160g. Because 20% of the weight was removed from a bite, we'll divide this weight by the percentage of the burger remaining after the bite:



80% of the burger is left after a bite. Convert this fraction into a decimal by dividing by 100:



Divide the initial weight by this decimal:



The weight of the burger before the second bite was 200.

We'll do the same procedure for the first bite. The initial weight is 200, and there is 80% of the burger remaining after the first bite. Because 80% is 0.8 in decimal form, divide 200 by 0.8:



The starting weight of the burger before the bites was 250 grams.