Question

at the school carnival reva sees a 6-l jar filled with marbles. the person who comes closest to guessing the number of marbles wins a bike. reva tries an expeirment and finds that 70 marbles can be placed in 250-ml cup. how many marbles should she guess are in the jar?

Answer 1

1,000 ml = 1 liter

6,000 ml = 6 liters

(6,000/250) * 70 = ?

Answer 2

"... Reva sees a 6-l jar filled with marbles....Reva tries an experiment, and finds that 70 marbles can be placed in 250-ml cup. How many marbles should she guess are in the jar?"

There is one significant digit in the "70 marbles" observation. Let's assume, therefore, that 70 ± 5 marbles can fit inside the 250-ml cup. Let us further assume that the 250-ml cup holds exactly 250.00 ml. Then:
(6 liters) x (70 ± 5 marbles per ¼-liter) = (6 liters) x (260 to 300 marbles/liter) = 1560 to 1800 marbles.

My experience says that there are 290 marbles per liter in a typical jar, so, MY answer of 6 x 290 = 1740 marbles is consistent with Reva's observations.

Answer: 1740 marbles.