Сысоева Елена 1/31+1/32+1/33+...+1/39+1/40>1/4, 1/31>1/40, 1/32>1/40, 1/33>1/40 и т.д.1/39>1/40 1/31+1/32+1/33+...+1/39+1/40>1/40+1/40+1/40+...+1/40+1/40=10/40=1/4 верно.
