Mean is 
and a standard deviation is 
, then the variable 
.
Use substitution
.
This substitution gives you that 
.
a. For X=130, 
and 
(the decimal value is taken from the Standard Normal Distribution Table).
b. For X=90, 
and for X=110, 
. Then 
(the decimal value is taken from the Standard Normal Distribution Table).
D. 21cm because you divide all sides by 2 then get your slope form and multiply by seven
Answer:
The answer is below
Step-by-step explanation:
Let x represent the cost of 1 scoop of ice cream. Since the cost of 2 scoops of ice cream are twice the price of 1 scoop of ice cream, therefore the cost of 2 scoops of ice cream = 2x
Jean buys 4 tubs with 2 scoops in them and 2 tubs with 1 scoop each. Therefore the money spent by Jean is:
Money spent by Jean = 4(2x) + 2(x) = 8x + 2x = 10x
Sarah buys 2 tubs of 2 scoops and 4 tubs of 1 scoop. The money spent by Sarah is:
Money spent by Sarah = 2(2x) + 4(x) = 4x + 4x = 8x
Sarah spends 2.50 € less than Jean. Therefore:
Money spent by Sarah = Money spent by Jean - 2.5
8x = 10x - 2.5
2x = 2.5
x = €1.25
Therefore the cost of 1 scoop of ice cream is €1.25, the cost of 2 scoops of ice cream is €2.50.
Money spent by Jean = 10x = 10(1.25) = €12.5
Money spent by Sarah = 8x = 8(1.25) = €10
Answer:
A number is a mathematical object used to count, measure and also label. The original examples are the natural numbers 1, 2, 3, 4 and so forth. A notational symbol that represents a number is called a numeral.
Answer:
x = 3/4
Step-by-step explanation:
Step 1: Write equation
5x - 2(x + 1) = 1/4
Step 2: Solve for <em>x</em>
- <u>Distribute -2:</u> 5x - 2x - 2 = 1/4
- <u>Combine like terms:</u> 3x - 2 = 1/4
- <u>Add 2 to both sides:</u> 3x = 9/4
- <u>Divide both sides by 3:</u> x = 3/4
Step 3: Check
<em>Plug in x to verify it's a solution.</em>
5(3/4) - 2(3/4 + 1) = 1/4
15/4 - 2(7/4) = 1/4
15/4 - 14/4 = 1/4
1/4 = 1/4
