Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 Write 92000 in scientific notation. (as a simplified expression)
Show worked solution
9.2 × 104.
2 Write 7500 in scientific notation. (as a simplified expression)
Show worked solution
7.5 × 103.
3 Write 4.5 × 103 as an ordinary number.
Show worked solution
4500.
Level 2 · Core
4 Write 0.0071 in scientific notation. (as a simplified expression)
Show worked solution
7.1 × 10−3.
5 Write 7.5 × 10−4 as an ordinary number.
Show worked solution
0.00075.
6 Is 15 × 106 correct scientific notation?
Show worked solution
No — 15 is not under 10. It should be 1.5 × 107.
Level 3 · Challenge
7 Which is larger, 4.2 × 105 or 8.9 × 104? (write the number part, like 4.2)
Show worked solution
4.2 × 105 (420,000) beats 8.9 × 104 (89000).
8 Work out (6 × 105) ÷ (1.5 × 10−2). (as a simplified expression)
Show worked solution
6 ÷ 1.5 = 4 and 5 − (−2) = 7, so 4 × 107.
9 Work out (8 × 106) × (2 × 103), in correct form. (as a simplified expression)
Show worked solution
16 × 109, adjusted to 1.6 × 1010.