Question 306277
Odds are given as favorable to unfavorable in simplest terms.
1:9 means 1 for (1/10), 9 against (9/10). Since there are 10 total, there is 1 algebra task, 9 non-algebra tasks. However since there are always twice as many probability tasks, then P=2. The remaining are geometry. 
1 A
2 P
7 G
.
.
.
1:4 means 1/5 are algebra, 10 slips total, 2 slips algebra. 2(2) probability, remainder geometry.
2 A
4 P
4 G
.
.
.
Watch the wording here.
3:2 means 3/5 are probability, 6 slips probability. (1/2)6 algebra, remainder geometry.
3 A
6 P
1 G