# Hug an Ancient Redwood Tree

Nice choice! Instead of potentially causing damage to a Sequoia tree, you've decided to show it some love. Hugging a tree is a great way to show your appreciation for nature.

The ancient now extinct Sequoias of this region have a diameter of about 10 to 12 feet (~3 meters) wide. In geometry, diameter refers to the straight line that crosses through the center of a circle (or body) and meets the circumference at each end. The circumference is the outer distance of a circle.

Now that you know about these basic mathematical concepts, complete the activities below.

For this activity:
1. You'll need a pencil, paper and calculator.
Like you would to the ancient Sequoias, show math some love too!

### Different Sizes, Different Perspectives

Near you, find the biggest object you can hug, maybe you have a giant teddy bear in your room. Can you wrap your arms entirely around it? Do your fingertips touch?
• Take a tape measure and wrap it around your object to see how wide it is in feet, which is a unit of measurement. Write down the distance around your object.

### Calculating the distance around a Redwood tree

To put this in perspective, here's a math riddle about the ancient Sequoias. As you approach a Sequoia Affinis tree, you see that it's about 12-feet wide in diameter. Using this value, find the distance around the tree.

• Use the formula for circumference: C = π d
• C is for circumference or the distance around.
• π is a unitless mathematical constant (3.14), which is the ratio of a circle's circumference to its diameter.
• d is for the diameter.
• In your calculator, multiply π by the diameter.

Think you know the answer? Check below! Compare this value to the widest object you were able to wrap your arms around. Do you think you'd be able to wrap your arms around an ancient or even a modern Redwood tree?

The distance around this Sequoia Affinis tree is about 37 feet!

### How many people does it take to wrap around a Redwood?

If several people came together, and each person had an arm span of 5-feet, then how many of them would have to hold hands to fully wrap around the trunk of our Sequoia Affinis tree?

Fun Fact:
If you extend your arms out horizontally (left and right), the length between your middle fingertips is the same as your height. This is an example of human body ratio.

About 7 people would need to hold hands around our tree!

To get this answer you have to divide the width around the Sequoia, which we calculated to be roughly 37 feet by 5-feet (the arm span length). The exact answer would be 7.4 people; however, you really can't have 0.4 of a person, so we rounded to 7 people.

### Great work!

Before making your next choice, learn about how the ancient Sequoias became petrified. Then, you can choose to either continue exploring the forest, revisit the Eocene, or return to the present.

Last updated: April 16, 2022