DINOSAURS By: Caroline Sangvai

REAL LIFE EXAMPLE Since dinosaurs roamed the earth a long, long time ago, paleontologists use exponents to describe how long ago they lived. Dinosaurs lived in the Mesozoic Era = Triassic Period, Jurassic Period, and Cretaceous Period. To describe their age, paleontologists need exponential notation because it is easier to use powers of ten for large numbers!

TRIASSIC PERIOD Dinosaurs lived throughout the Mesozoic Era which began 245 million years ago! The era is divided into 3 periods. The first Period is the Triassic Period. The Triassic Period was about 245 MILLION years ago! So in exponential notation, it would be 2.45 x 108. Can you see how writing in powers of ten, like 108, is easier than writing 100,000,000 and 245,000,000? This is a Coelophysis; it lived in the Triassic period

JURASSIC PERIOD After the Triassic Period ended, the Jurassic Period began. The Jurassic Period was about 208 MILLION years ago! In exponential notation 208,000,000 is 2.08 x 108. This is again a super easy technique! This is a Mamenchisaurus, it lived in the Jurassic Period. Its neck was 46 ft. long, or in exponential notation 4.6 x 101.

CRETACEOUS PERIOD The Cretaceous Period begins after the Jurassic Period. It is also the final period of the Mesozoic Era. It began 146 million years ago or 1.46 x 108 years ago. It ended 65 million years ago, or 6.5 x 107! By the end of this period dinosaurs were now known as extinct. More things started appearing like flowers, animals, and…Humans. This is a Tyrannosaurus Rex, it lived in the Cretaceous Period. It was known as the king of dinosaurs and dominated the period.

COMPARING DINOSAURS, HUMANS AND EXPONENTS The Mesozoic Era began 245 million years ago and then ended 65 million years ago. In exponential notation this is 2.85 x 108 and 6.5 x 107 years. Humans first appeared 100,000 or 1.0 x 105 years ago Creature How many years ago did they first appear? How many years after beginning of Mesozoic Era Triassic Dinosaurs 2.45x108 0 years, Triassic Period starts the Mesozoic Era Jurassic Dinosaurs 2.08x108 About the same as Triassic since both are 108 Cretaceous Dinosaurs 4.6x107 About 10 times as many years after Humans 1X105 About 1000 times as many years after or 103

CONCLUSION Exponential notation makes it easier to use large numbers Since dinosaurs lived millions of years ago, their age can be stated in exponential notation Exponential notation makes a lot of sense when studying events that occurred a long time ago. I enjoy working with powers of 10!

REFERENCES http://www.factmonster.com/ipka/A0878252.html https://en.wikipedia.org/wiki/Mesozoic