Please see also Tokaido Sanyo Shinkansen (Bullet train) fare table &
I went to Nagoya by a bullet train (Shinkan-sen). Bullet train's one way ticket cost 10980 yen ($113.20 €85.78) from Tokyo to Nagoya. Around August 15th, many people get their summer holiday. So this week is one of the highest traffic load season in the year. (The other season is New year's holiday.) I reserved my seat one month ago. It might be impossible to book a reserved seat on the day of the trip. You can buy a non-reserved seat ticket instead. In this case you may not be able to have a seat, but keep standing from Tokyo to Nagoya.
Kid's fare (applied to under 12-years-old) is the half of it.
Today's room temperature is over 32 C.