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