Answer:
The Answer is 400g. The work is shown down below. Hope this will help you out a little for you to understand it.
Explanation:
five block weight is 3kg
The 4th block of each weight is 650
The total of 4 blocks equals 650 times 4 equals 2600 gram
each kg=1000 gram
The five blocks: 3 times 1000=3000 gram.
the fifth block weighs equal 3000 subtract 2600 equals 400 grams
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