Б) (30-1)(30+1) = (30²-1²) = 900-1 = 899
в) (60-1)(60+1) = (60²-1²) = 3600-1 = 3599
г) (100-1)(100+1) = (100²-1²) = 10000 - 1 = 9999
д) (20-2)(20+2) = (20²-2²) = 400-4 = 396
е) (50-2)(50+2) = (50²-2²) = 2500-4 = 2496
4кг=b
1кг=1/4b
6кг=6/4b=1.5b
Пусть Ёжа-а. Чиж-b , Бобр- cа=2b c=5bc=b+85b=b+84b=8b=2a=2*2=4c=5*2=10<span>a+b+c=2+4+10=16 долек было в апельсине
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