## Thinking Mathematically (6th Edition)

The year when America declared Independence is $1776$
The Roman Numeral written along the base of the pyramid at the back of US one dollar is MDCCLXXVI Converting MDCCLXXVI to Hindu Arabic Numeral, we get \begin{align} & 1000+500+100+100+50+10+10+5+1=1000+700+70+6 \\ & =1776 \end{align} Which is the year when America declared Independence. After Observing and calculating the back of US one dollar, we find the year $1776$ written in Roman Numerals along the base of the pyramid