Let daniel's age = d and let jessica's age = j
let your current age = x and your wife's current age = y
x = 5d (given in question)
∴ x - 5d = 0
x + 21 = 2(d+21) (given in question)
∴ x + 21 = 2d + 42
∴ x - 2d = 21
We can solve these two rearranged equations simultaneously by multiplying the first equation by -1 and adding them. This gives us the following:
3d = 21
∴ d = 7
This means that daniel is currently 7 and (if we substitute d = 7 into one of the equations) you are 35. We use a similar method for your wife's and jessica's current ages.
y = 7j (given in question)
∴ y - 7j = 0
y + 8 = 3(j + 8)
∴y + 8 = 3j + 24
∴ y - 3j = 16
If we use a similar method of elimination we get this:
4j = 16
∴ j = 4
Hence, from this we can concur that daniel is 7 and jessica is 4.
Answer:
To make the cup 64.57 square inches of plastic were used.
Step-by-step explanation:
A cup has the format of a cylinder with a open top. The surface area of the cup is given by the area of it's base (a circle) and the area of it's walls, wich can be seen as rectangle where the width is the length of the circle at the base and the height is the height of the cylinder. So we have:
area of the base = pi*r^2 = 3.14*(1.75)^2 = 3.14*3.0625 = 9.616 square inches
area of the walls = 2*pi*r*h = 2*3.14*(1.75)*5 = 54.95 square inches
surface area of the cup = area of the base + area of the walls = 9.616 + 54.95
surface area of the cup = 64.57 square inches
To make the cup 64.57 square inches of plastic were used.
The system of inequalities would be:
L+M >= 500 (greater than or equal to)
2L + 0.5M <= 850 (less than or equal to)
The first inequality deals with the total number of balloons. She wants the total to be at least 500, so add the variables and set it greater than or equal to 500.
The second inequality deals with the helium. 2L comes from each latex balloon using 2 ft^3 of helium. 0.5M comes from each Mylar balloon using 0.5 ft^3. Together they can use no more than 85% of the 1000 ft^3 tank; 85% = 0.85; 0.85×1000=850. "No more than" tells us it must be less than or equal to.
As the key suggests, the left part is the integer part of the number, while the digit on the right is the decimal part of the number.
So, for example, the first row describes the two values 97.2 and 97.8, while the second row describes the values 98.1, 98.3 (repeated twice), 98.5, 98.6 and 98.7 (repeater three times).
So, the number of values is given by the number of leaves: you simply have to count how many digits are there on the right part of the screen.
The answer is thus 24
Thicknesses at different point are: <span>41, 38, 36, 29, 34, 44, 46, 43, 35, 40
In increasing order: 29, 34, 35, 36, 38, 40, 41, 43, 44, 46
Median = (38+40)/2 = 39m</span>
Median thickness is 39m
