Machine A makes 70% of the items and one in ten of its items is faulty. Machine B makes 30% of the items and one in five of its items is faulty.
Machine	Share of items made	Fraction faulty
A	$70\%$	$\frac1{10}$
B	$30\%$	$\frac15$

Route R is chosen with probability two thirds and has six covered and six uncovered stops. Route S is chosen with probability one third and has three covered and one uncovered stop.
Route	Probability of choosing route	Covered stops	Uncovered stops
R	$2/3$	6	6
S	$1/3$	3	1

Route R is chosen with probability two thirds and has six covered and six uncovered stops. Route S is chosen with probability one third and has three covered and one uncovered stop.
Route	Probability of choosing route	Covered stops	Uncovered stops
R	$2/3$	6	6
S	$1/3$	3	1

Folder M has one sheet with a diagram and three without. Folder N has three sheets with a diagram and three without.
Folder	Sheets with a diagram	Sheets without a diagram
M	1	3
N	3	3

Folder M has one sheet with a diagram and three without. Folder N has three sheets with a diagram and three without.
Folder	Sheets with a diagram	Sheets without a diagram
M	1	3
N	3	3

Lesson 1

Which outcomes still count?

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