For an instance, i stands for the money that you have, and b stands for the money that brother has.
An equation system based on the problem would be
i + b = 42 (equation 1)
i = 3b (equation 2)
Use substitution method to solve the problem
substitute 3b into i in the equation 1
i + b = 42
3b + b = 42
4b = 42
b = 42/4
b = 10.5
substitute the value of b into the equation 1
i = 3b
i = 3(10.5)
i = 31.5
You have $31.5 and your brother has $10.5
$20*5=$100 (for the jeans)
$10*5=$50 (for the t-shirts)
$100+50=$150
Anna was able to buy 5 pairs of jeans and 5 T-shirts, for $150.
We can conclude that All the data points are exactly the same. When we calculate one variable statistic and we find that the standard deviation is equal to zero most likely that we can conclude is that all the data points will be exactly the same.
5g + 3(-7 + 5g) = 1 - g
5g - 21 + 15g = 1 - g
20g - 21 = 1 - g
20g + g = 1 + 21
21g = 22
g = 22/21 <===
