2 Unit 2: Applied Mathematics A

The number of faults found on each of 70 cars is summarised in the table below, where $a\,$ and $b\,$ are positive integers.

Number of faults	0	1	2	3	4
Frequency	12	$a$	20	$b$	6

The mean number of faults per car is exactly 2.

a.

Show that $a + b = 32$ and $a + 3 b = 76$ .

[3]

b.

Find the value of $a\,$ and the value of $b$ .

[2]

c.

Write down the mode of the number of faults.

[1]

The number of faults found on each of 70 cars is summarised in the table below, where $a\,$ and $b\,$ are positive integers.

Number of faults	0	1	2	3	4
Frequency	12	$a$	20	$b$	6

The mean number of faults per car is exactly 2.

a.

Show that $a + b = 32$ and $a + 3 b = 76$ .

[3]

b.

Find the value of $a\,$ and the value of $b$ .

[2]

c.

Write down the mode of the number of faults.

[1]

2 Unit 2: Applied Mathematics A Questions