Answer:
the fifth block weighs = 3000-2600 = 400 gram
Step-by-step explanation:
five blocks weigh : 3 kg
4 blocks each weighs 650
total of 4 blocks= 650*4=2600 gram
each kg=1000 gram
five blocks: 3*1000=3000 gram.
the fifth block weighs = 3000-2600 = 400 gram