Answer:
A variable is a quantity that may change within the context of a mathematical problem or experiment. ... The letters x, y, and z are common generic symbols used for variables. Sometimes, we will choose a letter that reminds us of the quantity it represents, such as t for time, v for voltage, or b for bacteria.
Step-by-step explanation:
thats true❤️
You can extract two balls of the same colour in two different way: either you pick two black balls or two red balls. Let's write the probabilities of each pick in each case.
Case 1: two black balls
The probability of picking the first black ball is 2/5, because there are two black balls, and 5 balls in total in the urn.
The probability of picking the second black ball is 1/4, because there is one black ball remaining in the urn, and 4 balls in total (we just picked the other black one!)
So, the probability of picking two black balls is

Case 2: two red balls
The probability of picking the first black ball is 3/5, because there are three red balls, and 5 balls in total in the urn.
The probability of picking the second red ball is 2/4=1/2, because there are two red balls remaining in the urn, and 4 balls in total (we just picked the other red one!)
So, the probability of picking two red balls is

Finally, the probability of picking two balls of the same colour is

Answer:
6 days ; 2300 calories
Step-by-step explanation:
Given the following :
Current consumption :
Simba = 1520 calories per day
Increases by 130 calories per day : After d days ;
S(d) = 1520 + 130d
Where ; d = number of days
Cuddle = 3380 calories
Decreases by 180 calories each day; after d days ;
S(d) = 3380 - 180d
Pattern continues until they both consume same number of calories each day
S(d) = C(d)
1520 + 130d = 3380 - 180d
130d + 180d = 3380 - 1520
310d = 1860
d = 6
Number of calories they will be consuming them ;
Using : S(d) = 3380 - 180d
S(6) = 3380 - 180(6)
S = 3380 - 1080
S = 2300
They will be consuming 2300 calories by then.