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2 years ago

Describe how to model 2 digit by 2 digit multiplication using an area model

1 answer:

7 0

Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models. hope that helped

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Marissa has a photograph that measures 2 in. by 4 in. She has mounted the picture on a mat so that there is a border that measur

Ket [755]

Step-by-step explanation:

The initial image of the photo is 2 in by 4 in. The mat is 4 in by 6 in.

The new image is dilated by a scale of 2. So we double the dimensions. The new photo is 4 in by 8 in. The new mat is 8 in by 12 in.

7 0

3 years ago

Rabies is a viral disease of mammals transmitted through the bite of a rabid animal. The virus infects the central nervous syste

lisabon 2012 [21]

Answer:

(a) The value of x is 0.30.

(b) The probability that a reported case of rabies is not a raccoon is 0.45.

Step-by-step explanation:

Denote the events as follows:

R = reported case of rabies is a raccoon

F = reported case of rabies is a fox

B = reported case of rabies is a bat

O = reported case of rabies is a some other animal.

The data provided is:

P (R) = 0.55

P (F) = 0.11

P (B) = 0.04

P (O) = x.

(a)

A property of a probability distribution is that the sum of all individual properties is 1.

That is, $\sum P(X)=1$

Compute the value of x as follows:

$\sum P(X)=1\\P(R)+P(F)+P(B)+P(O)=1\\0.55+0.11+0.04+x=1\\0.70+x=1\\x=1-0.70\\x=0.30$

Thus, the value of x is 0.30.

(b)

The probability of the complement of an event is the probability of its not happening.

$P(A^{c})=1-P(A)$

Compute the probability that a reported case of rabies is not a raccoon as follows:

$P(R^{c})=1-P(R)\\=1-0.55\\=0.45$

Thus, the probability that a reported case of rabies is not a raccoon is 0.45.

(c)

Compute the probability that a reported case of rabies is either a bat or a fox as follows:

$P(B\cup F)=P(B)+P(F)\\=0.11+0.04\\=0.15$

Thus, the probability that a reported case of rabies is either a bat or a fox is 0.15.

4 0

2 years ago

Sugar was traditionally produced and sold as sugarloaves, which are cones of sugar wrapped in paper. Find the total surface area

Zolol [24]

Answer:

A = 326,73 cm²

Step-by-step explanation:

The area of a circular cone is area of the base (A₁ ) plus area lateral ( area of a circular sector of radius the slant height )

Then we proceed to calculate the area of the base A₁

diameter of circular base is 8 cm then the radius is 4 cm and the area is:

A₁ = π*r² = 3,14* (4)²

A₁ = 3,1416*16 = 50,2656 cm²

Now Lateral area of the cone (A₂) is equal to the area of a circular sector with radius the slant height. We will calculate it, taken into account that this circular sector is part of a circle of radius the slant height.

Between the area of circular sector with radius the slant height and the area of the circle with the same radius there is a linear relation. That is we can calculate area of a circular sector by rule of three as follows:

The length of the circular sector is the length of the circle of the base of the cone, that is:

L = 2*π*(4)

L = 2*3,1416*4

L = 25,1328 cm

Then we have a circular sector of length 25,1328 cm

The area of the circle of radius 22 cm is:

A(c) = π*(22)² ⇒ A(c) = 1520,5344 cm²

And the length of this circle is:

L(c) = 2*π*(22) ⇒ 138,2304 cm

Then we apply a rule of three

For a length of 138,2304 cm ⇒⇒⇒ (area) 1520,5344 cm²

Then for a length of 25,1328 cm ⇒⇒⇒(area) A₂ (??)

Therefore:

A₂ = (25,1328)*1520,5344)/ 138,2304

A₂ = 276,4608 cm²

Then total area of the cone is:

A = A₁ + A₂

A = 50,2656 +276,4608

A = 326,7264 cm²

Round answer A = 326,73 cm²

8 0

2 years ago

Read 2 more answers

The manager of a snack bar buys bottled water in packs of 35 and candy bars in packs of 20. Then, she sells the items individual

hoa [83]

Answer:

8 packs of bottled water and 14 packs of candy bars

Step-by-step explanation:

Provided,

Each pack of water bottles = 35 bottles

Each pack of candy = 20 candy

Since quantity of candy in each pack is small than quantity of water bottle in each pack, in order to have same quantity in numbers of both bottles and candies,

Purchase quantity of candy packs shall be more than the pack of water bottles.

Further, with this option 1 and 2 are not valid as candy packs are same or less than packs of water bottle.

In option 3 and 4, option 3 have smaller quantities as provided manager bought the least possible quantity.

Accordingly

Option 3

8 packs of water bottle = $8 \times 35 = 280 \ water\ bottles$