Work out (3.5 x 104) x (2.2 x 10-3). Give your answer in standard form.
(Total for Question 3 is 2 marks)
4
Work out (6.0 x 107) / (2.5 x 103). Give your answer in standard form.
(Total for Question 4 is 2 marks)
5
Work out 4.2 x 106 + 3.6 x 105. Give your answer in standard form.
(Total for Question 5 is 2 marks)
6
Estimate the product of 9.8 x 102 and 4.05 x 10-1 to 2 significant figures. Give your answer in standard form.
(Total for Question 6 is 2 marks)
7
Show that if 2.5 x 10-3 x = 6.25 x 101 then x = 2.5 x 104.
(Total for Question 7 is 3 marks)
8
Which is larger, 3.6 x 108 or 2.9 x 109? Explain your answer briefly.
(Total for Question 8 is 1 mark)
9
The luminosity of a distant star is 3.2 x 1026 W. The luminosity of the Sun is 3.828 x 1026 W. Find the ratio star : Sun to 2 significant figures and give your answer in standard form.
(Total for Question 9 is 3 marks)
10
A quantity y and x are related by y/x = k, where when x = 3.2 x 103, y = 6.4 x 10-2. Work out k and give your answer in standard form.
(Total for Question 10 is 4 marks)
11
Write 0.000000432 in engineering notation (a power of 10 with exponent a multiple of 3).
(Total for Question 11 is 2 marks)
12
Given A = 5.12 x 103 and B = 3.87 x 102, calculate (A + B) / (A - B). Give your answer to 4 significant figures.
(Total for Question 12 is 4 marks)
Mark scheme · 5.4H Standard Form: Higher Tier Practice
Question 1
B1 7.42 x 10-4 cao
Answer: 7.42 x 10-4
Question 2
B1 406000 cao
Answer: 406000
Question 3
M1 multiply coefficients and add powers: 3.5 x 2.2 and 104 + -3 method
A1 7.7 x 101 cao
Answer: 7.7 x 101
Question 4
M1 divide coefficients and subtract powers: 6.0/2.5 and 107 - 3
A1 2.4 x 104 cao
Answer: 2.4 x 104
Question 5
M1 convert to same power of 10 and add (e.g. 4.2 x 106 + 0.36 x 106 or equivalent shown)
A1 4.56 x 106 cao
Answer: 4.56 x 106
Question 6
M1 multiply the numbers: 9.8 x 4.05 x 102 + -1 or equivalent method
A1 4.0 x 102 cao (396.9 rounded to 2 s.f.)
Answer: 4.0 x 102
Question 7
M1 divide both sides by 2.5 x 10-3 showing 6.25/2.5 and 101 - -3 or equivalent
M1 evaluate 6.25/2.5 = 2.5
A1 2.5 x 104 cso
Answer: 2.5 x 104
Question 8
B1 2.9 x 109 is larger, because exponent 9 > 8 so it is 10 times larger order of magnitude oe
Answer: 2.9 x 109 is larger because its power of 10 is greater (109 vs 108).
Question 9
M1 divide 3.2 x 1026 by 3.828 x 1026 or show equivalent calculation
M1 evaluate ratio 3.2/3.828 = 0.8360... shown
A1 8.4 x 10-1 cao (0.84 to 2 s.f.)
Answer: 8.4 x 10-1
Question 10
M1 substitute and divide: k = (6.4 x 10-2) / (3.2 x 103) shown
M1 divide coefficients 6.4/3.2 = 2.0 and subtract exponents -2 - 3 = -5 or equivalent exponent step
A1 2.0 x 10-5 cao
B1 statement that k = 2.0 x 10-5 (coefficient in standard form between 1 and 10) oe
Answer: 2.0 x 10-5
Question 11
M1 express number with exponent multiple of 3, e.g. move decimal to give 432 x 10-9 shown
A1 432 x 10-9 cao
Answer: 432 x 10-9
Question 12
M1 convert to ordinary numbers or show sum and difference in standard form: A + B = 5120 + 387 and A - B = 5120 - 387
M1 evaluate sum 5507 and difference 4733 or show correct intermediate values
A1 5507 / 4733 = 1.163532... correct to at least 4 s.f.
A1 1.164 cao (answer rounded to 4 significant figures)