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2 years ago

What is (3×10) ×8= ------ × (10×8) elementary 5th grade

Mathematics

2 answers:

ipn [44]2 years ago

8 0

Using the property $(a\times b) \times c = a \times (b\times c)$ , we know that 3 is the missing number.

Tamiku [17]2 years ago

4 0

This is an example of the commutative property of multiplication.

That property states: $(a \times b) \times c = a \times (b \times c)$

So using that property, we can figure out that 3 should be in the blank.

You might be interested in

Compare the line passing through the points (−3, −11) and (6, 4) to the line given by the equation y=35x−6.

Aleks04 [339]

Let
A------> (−3, −11)
B------> (6, 4)

step 1
find the slope m point A and point B
m=(y2-y1)/(x2-x1)-----> m=(4+11)/(6+3)----> m=15/9---> 5/3

step 2
with m=5/3 and point B (6, 4) find the equation of a line
y-y1=m*(x-x1)-----> y-4=(5/3)*(x-6)---> y=(5/3)x-6

case a. they have the same slope------> is not correct
because
y=35x−6------> the slope m=35
y=(5/3)x-6---> the slope m =5/3

case b. they have the same x-intercept.----> is not correct
because
the x-intercept is for y=0

y=35x−6-----> 0=35x-6----> 35x=6-----> x=6/35
the x-intercept is the point (6/35,0)

y=(5/3)x-6----> 0=(5/3)x-6----> (5/3)x=6---> x=18/5
the x-intercept is the point (18/5,0)

case c. the two lines are perpendicular. do. they have the same y-intercept-----> is nor correct
because

if two lines are perpendicular
m1*m2=-1-------> this condition is not satisfied

the y intercept is for x=0

y=35x−6-------> y=-6
the y intercept is the point (0,-6)

y=(5/3)x-6-----> y=-6
the y intercept is the point (0,-6)

they have the same y-intercept but the two lines are not perpendicular

see the attached figure

7 0

3 years ago

Drag each rational number to the correct location on the table.

andrey2020 [161]

Answer:

Step-by-step explanation:

Positive: -1/-3, -2/-2, +2/+3, -1/+3

the rest of them are negative

3 0

2 years ago

Voltage sags and swells. The power quality of a transformer is measured by the quality of the voltage. Two causes of poor power

zysi [14]

Answer:

$z-score = 1.57$

$z-score_s = -3.36$

Step-by-step explanation:

From the question we are told that

The sample size is n = 103

The sample mean of sag is $\= x_1 = 353$

The sample mean of swells is $\= x_2 = 184$

The standard deviation of sag is $s_1 = 30$

The standard deviation of swells is $s_2 = 25$

The number of swell for a randomly selected transformer is k = 100

The number of sag for a randomly selected transformer is c = 400

Generally the z-score for the number of swells is mathematically represented as

$z-score_s = \frac{ k - \= x_2}{s_2}$

=> $z-score_s = \frac{ 100- 184}{25}$

=> $z-score_s = -3.36$

Generally the z-score for the number of sags is mathematically represented as

$z-score = \frac{ c - \= x_1}{s_1}$

$z-score = \frac{ 400 - 353}{30}$

$z-score = 1.57$

4 0

3 years ago

Can someone please answer 5, 6 and 7? Thank you.

Montano1993 [528]

Reduce a 24 cm by 36 cm photo to 3/4 original size.

The most logical way to do this is to keep the width-to-height ratio the same: It is 24/36, or 2/3. The original photo has an area of (24 cm)(36 cm) = 864 cm^2.

Let's reduce that to 3/4 size: Mult. 864 cm^2 by (3/4). Result: 648 cm^2.

We need to find new L and new W such that W/L = 2/3 and WL = 648 cm^2.

From the first equation we get W = 2L/3. Thus, WL = 648 cm^2 = (2L/3)(L).

Solve this last equation for L^2, and then for L:

2L^2/3 = 648, or (2/3)L^2 = 648. Thus, L^2 = (3/2)(648 cm^2) = 972 cm^2.

Taking the sqrt of both sides, L = + 31.18 cm. Then W must be 2/3 of that, or W = 20.78 cm.

Check: is LW = (3/4) of the original 864 cm^2? YES.

6 0

3 years ago

Find the measure of angle x

Triss [41]

Answer:

it is heptagon and sum of interior angles of heptagon is 900 °

123°+131°+ 125°+124°+x 129°+132° = 900°

764° +x = 900 °

x = 900°-764°

x = 136°

4 0

3 years ago