Imagine, at the first day you have only one penny. Then tomorrow you have 2 pennies, next day you have 4 (2x2), next day you have 8 (4x2), next day you have 16 (8x2).... and so forth.
It looks like geometric sequence isn't it? (the ratio between the number of pennies that you have from the 2nd day and the 1st day is 2)
So, by using geometric sequence theorem we can total those pennies until day-27
S (total pennies at day-27) = (1)(2^27-1) / 2-1 = 2^26 pennies
So, you have 2^26 pennies.. a big number of pennies huh?=))
{The formula is: S = a( r^n-1) / r-1
Where:
a= the number of pennies that you've got at the 1st day
n= number of days you spent to collect those pennies)
r= the ratio of the number of pennies}
False. You can find the solution more quickly by solving the system algebraically.
-4x + 2y = 18
Since y=-3x+4,
-4x + 2(-3x+4) = 18
-4x - 6x + 8 = 18
-10x = 10
x = -1
y = -3x+4 = 7
1/15
1/9:5/3 = 3/45:1
3:45 = 1/15
Answer:
Number 1 would be figure 2
Number 2 would be figure 1
Number 3 would be figure 3
Step-by-step explanation:
A correlation coefficient describes the relationship between two variables. A zero shows that there is no correlation while a one describes a positive correlation. A negative one describes a negative correlation. Since all of the dot in the scatter plot in figure 2 are spread out and not in a line, it has no correlation or you could say that it's coefficient is zero. Since the dots in figure 1 are going from left to right and are close together, it has a positive correlation. Since the dots in figure three are going right to left and resemble a line, the correlation coefficient is -1.