Step-by-step explanation:
Sn=n/2(2a+(n-1)d)
910=n/2{2a+(n-1)d}
1820=n{2a+(n-1)d}
1820=20{2a+(20-1)d}
1820=20{2a+19d}
91=2a+19d
An=a+(n-1)d
95=a+(20-1)d
95=a+19d
91=2a+19d
---------------
4=-a
a=-4
91=2a+19d
91=2(-4)+19d
91=-8+19d
91+8=19d
99=19d
d=99/19
A=-4
Step-by-step explanation:
1st way: 5x
2nd way: 5.x
third way: 5(x)
Answer:
72 cents.
Step-by-step explanation:
The expected winnings is the amount times the probability that you will get that amount.
2,000 * (1/10,000) = 2,000 / 10,000 = 2 / 10 = 0.2.
700 * (4 / 10,000) = 2,800 / 10,000 = 28 / 100 = 0.28.
300 * (8 / 10,000) = 2,400 / 10,000 = 24 / 100 = 0.24.
0.2 + 0.28 + 0.24 = 0.72.
Hope this helps!
