Answer:
D.
Step-by-step explanation:
It just is hard to explain but I had the same question.
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
They're trying to trick you with √2. Remember in the 30/60/90 triangle the sides are in ratio 1:√3:2, with the "1" opposite the 30 degrees.
Here we have
1:√3:2 = 6√2:x:hypotenuse
or
x/(6√2) = √3/ 1
x = 6√2×√3 = 6√6
Answer: AC=6√6
We have three numbers to arrange so that 6 is 1/10 of the value of the other six.
Since position tells us whether we're talking about single, tens, hundreds, thousands (e.g. 25 is two times 10 plus five times 1) we know that the two sixes must be next to each other.
This leaves us with two options.
663 or 366.
In each of these cases the second 6 in the number is one tenth of the first 6.
If we look at the only other option: 636 we see that the second 6 is one hundredth of the value of the first 6.
