Standard form：练习题

Write the number \(650,000,000\) in standard form.

Calculate the value of \((1.2 \times 10^5) + (3.4 \times 10^4)\).
Give your answer in standard form.

Express the number \(0.000082\) in standard form.

Work out \(\frac{4.5 \times 10^7}{5 \times 10^{-2}}\).
Give your answer in standard form.

A rectangular field has a length of \( 6.4 \times 10^2 \) metres and a width of \( 5 \times 10^1 \) metres.

Calculate the area of the field.
Give your answer in standard form.

Express the number \(0.0000037\) in standard form.

A beam of light travels at a speed of \(3 \times 10^5\) km/s. Calculate the time, in seconds, it takes for the light to travel a distance of \(4.5 \times 10^7\) km. Give your answer in standard form.

Write the number \(5.4 \times 10^4\) as an ordinary number.

A spaceship travels at a constant speed of \(2.4 \times 10^4\) kilometres per hour.

(a) Calculate the distance the spaceship travels in 15 hours. Give your answer in standard form.

(b) The distance from Earth to a satellite is \(3.6 \times 10^5\) km. Calculate the time it takes for the spaceship to reach the satellite. Give your answer in hours.

The mass of Planet X is \(6 \times 10^{24} \text{ kg}\). The mass of Planet Y is \(1.5 \times 10^{27} \text{ kg}\).

(a) Calculate how many times heavier Planet Y is than Planet X. Give your answer in standard form.

(b) Find the total mass of Planet X and Planet Y. Give your answer in standard form.