Area of a regular octagon with radius 8

Drew is 3 years younger than his brother, Jimmy. The sum of the brothers' ages is 21 1. Draw a bar model to represent this situa

alina1380 [7]

The first step to solving a story problem is identifying variables. For this problem, I will identify the variables as:

D = Drew's age

J = Jimmy's age

Once the variables are identified, we need to find as many equations as we have variables. Since we have two variables, we will have to write two equations.

Since Drew is 3 years younger than Jimmy: D + 3 = J

Since the sum of the brothers' ages is 21: D + J = 21

Once I have two equations is two variables, I can solve the system using either substitution method or elimination method. For this problem, I will use substitution method.

D + J = 21 Equation 2

D + (D + 3) = 21 Substitution of value of J from equation 1 into equation 2

D + D + 3 = 21 Associative property of addition

2D + 3 = 21 Simplify

2D + 3 - 3 = 21 - 3 Subtract 3 from each side

2D = 18 Simplify each side

2D/2 = 18/2 Divide each side by 2

D = 9 Simplify each side

Now that we have D, we can substitute it into equation 1 to get the value of J

D + 3 = J Equation 1

9 + 3 = J Substitution

12 = J Simplify

7 0

3 years ago

I can’t figure it out!! Please help me!

Vadim26 [7]

Answer:

height = 8 cm

Step-by-step explanation:

formula to find area of a parallelogram =

base x height

so

10 x height = 80 cm square.

height = 80/10

=8 cm

3 0

2 years ago

Centerpieces are normally distributed with mean of 30 ounces and standard deviation of 2 ounces. The weights of the shipping box

astraxan [27]

Answer:

0.0901 = 9.01% of packages will incur such a charge

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Sum of normal variables:

When we add normal variables, the mean will be the sum of the means, while the standard deviation is the square root of the sum of the variances.

Centerpieces are normally distributed with mean of 30 ounces and standard deviation of 2 ounces.

This means that $\mu_C = 30, \sigma_C = 2$