A moon is about 240,000 miles from the planet orbits.

Question

(a) Write this number in scientific notation.

(b) If a rocket at 6 x 10^4 miles per hour, how long would it take for it to reach the moon from the planet.

(Use the multiplication symbol in the math palette as needed)

Answer 1

a.  To convert to standard notation, move the decimal point so that it is after the first non-zero number and count how many places the decimal moved.  The number of places that the decimal point moves is the exponent on the power of ten.  If the decimal moves to the left, the exponent should be positive.  If the decimal moves to the right, the exponent should be negative.

Since the decimal is moving 5 places to the left in this problem, the exponent on 10 will be 5.

2.4 X 10⁵ miles

b.  v = x/t                           Formula for velocity

vt = x                                Multiply both sides by t

t = x/v                               Divide both sides by v

t = (2.4 X 10⁵)/(6 X 10⁴)     Substitute in the values of the variables

t = 2.4/6 * 10⁵/10⁶             Group the constants and the powers of ten

t = .4 * 10                         Simplify the fractions

t = 4 hours                         Multiply the remaining power of 10