Answer:
P(n,4)÷P(n,2)
= (n-2)(n-3)
20 = 4 × 5 (two consecutive numbers)
(n-2)(n-3)=5×4
n-2=5
n=7
Answer:
<em>There are 12 students.</em>
Step-by-step explanation:
This is because there are 4 students per team, and there is 3 teams.
So...
3 * 4 = 12 students
Answer:
1/2a-19=-13
Step-by-step explanation:
One half of a number represents the phrase "1/2a" (in this case the variable/number is 'a'". Then because it says "nineteen less than", that means you subtract 19 from one half of the variable.
Using the Sine Rule:-
20 /sin 45 = BC / sin 30
BC = 20 sin 30 / sin45
= 20 * 1/2 / 1 / sqrt2
= 20 * 1/2 * sqrt2
= 10 sqrt2 answer
