The oldest president on this list is John Tyler, the 10th US President, who took office in 1841 at the age of 51, after the passing of President William Henry Harrison. He became the first vice president to assume office due to the death of a sitting president. After serving one term, he left office at the age of 55.

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As mentioned earlier, the average age of US presidents at the time of inauguration is 55. Surprisingly, this president took office at just 50, five years younger than the average! We're talking about Millard Fillmore, the 13th president of the United States. Although he was not elected, he assumed the presidency on July 9, 1850, following the death of President Zachary Taylor, and left office 3 years later at the age of 53.

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In 1825, James K. Polk became the 11th US president, taking office at the age of 49. During his campaign and time in office, he stated that he would serve only one term, and he kept his promise by not seeking re-election. Fun fact: At the time of his election, Polk was the youngest person ever chosen as president of the United States.

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Just like Polk, James A. Garfield also became president at the age of 49. At the time of his inauguration in 1881, Garfield was not the youngest ever elected, but he was the youngest Republican to become president! And that's not all: He was also the first left-handed person to serve, though it is said that he could write with both hands!

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Franklin Pierce may not be the most popular president in US history, but he was one of the youngest ever to hold office.

When Pierce took office in 1853, he was 48 years old. His presidency was marked by political tensions and personal tragedy. Serving only one term, he left office at the age of 52.

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In 2009, Barack Obama became the 44th President of the United States at just 47 years old. After serving two consecutive terms, he left office at 55. As you can see, he left office at an age when many typically start their presidency! Additionally, Obama was born in 1961, which makes him the first president born in the 1960s.

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Ulysses S. Grant became the 18th President of the United States in 1869 at just 46 years old. He served two terms and left the presidency at 54, still quite young for a former president.

Perhaps it was precisely his youth that led to a rather amusing incident. President Grant, a well-known horse enthusiast, received a speeding ticket in 1872... On horse! He was racing a horse-drawn carriage in Washington, DC, and ended up paying a $20 fine.

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The '90s may feel like just yesterday, but believe it or not, more than 30 years have passed since that decade began! However, we're sure you remember this event well: On January 20, 1993, Bill Clinton was inaugurated as the US President at just 46 years old. Like Grant, he served two terms and left office at 54.

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John F. Kennedy took office as the 35th US President on January 20, 1961, at just 43 years old, making him the youngest elected president in US history!

Although his presidency was tragically short, it was marked by major milestones. Kennedy set a goal for America: to be the first nation to land a man on the moon before the end of the 1960s. Although he sadly didn't live to see it, his words became a reality when Apollo 11 landed on the moon in 1969!

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We've reached the youngest president, not just on this list but in all of US history! That title goes to Theodore Roosevelt, who became the 26th president in 1901 at just 42 years old.

While he first took office in 1901 following the death of President William McKinley, Teddy Roosevelt was officially elected in 1904 and began his second term in 1905.

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