30 Jagged rocks are the same 3 shiny rocks using the exchange rates provided(i.e. option D)
What is an exchange rate?
Exchange rate means the rate at which one item exchanges hands with another, for instance, in this case, 6 jagged rocks are equivalent to 2 smooth pebbles.
6 jagged rocks=2 smooth pebbles
divide both sides by 2
6/2 jagged rocks=2/2 smooth pebbles
3 jagged rocks=1 smooth pebble
We can rewrite as below:
1 jagged rock=1/3 smooth pebble
30jagged rocks=1/3*30 smooth pebbles
30 jagged rocks=10 smooth pebbles
Now we need to convert 10 smooth pebbles to shiny rock equivalence
3 smooth pebbles=1 shiny rock
1 smooth pebble=1/3 shiny rock
10 smooth pebbles=1/3*10 shiny rocks
10 smooth pebbles=3 shiny rocks( even though it is 3.33, but the final answer should be rounded to a whole number)
Read more about exchange rate in the link below:
brainly.com/question/2202418
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