Question

On July 4, 2020, America turned 7.69 x 10^9

Answer 1

America's age = 243.85 years

Further explanation

When converting units, list and multiply all the units until you find the unit you want

Time unit conversion

1 year = 365 days

1 day = 24 hours

1 hour = 3600 s

7.69 x 10⁹ seconds to years :

$\tt =7.69\times 10^9~s\times \dfrac{1`hour}{3600~s}\times \dfrac{1~day}{24~hours}\times \dfrac{1~years}{365~days}\\\\=\dfrac{7.69\times 10^9}{3600\times 24\times 365}\\\\=\boxed{\bold{243.85~years}}$