All categories

3 years ago

The mean of 5 numbers is 50 and the mean of 4 of this numbers is 45. What is the fifth number

Mathematics

1 answer:

Kitty [74]3 years ago

7 0

Answer:

the fifth number is 70

Step-by-step explanation:

mean (average) of first 5 numbers =50 , Then sum of this 5 numbers = 50*5 =250.

The mean of 4 numbers = 45 . Sum 4 numbers = 45*4 = 180

the fifth number is 250-180=70

(180 +70)/5=50 which is the mean

You might be interested in

If one of the acute angles of a right angled triangle is 55 , calculate the remaining angle

lions [1.4K]

Answer:

35 degrees

Step-by-step explanation:

To start off, the term "acute angle" means less than 90 degrees. In this case, the acute angle is 55 degrees.

The type of triangle mentioned in the question is a right-angled triangle, meaning it has a right triangle (90 degrees) along 2 other triangles. A triangle is generally 180 degrees. So now that we know the value of 2 out of 3 angles we do simple math.

Assume the unknown angle is A.

55 + 90 + A = 180

A = 35

8 0

3 years ago

Jenny wants a total of 12 barbies dolls by the time she is 9 years old. Right now she has 4 barbie dolls. How many more does she

earnstyle [38]

A because 8+4=12 therefore x=8

3 0

3 years ago

Read 2 more answers

PLZ HELP, GIVING BRAINLIEST!

mote1985 [20]

Answer:

d) (-3/2, -1/2)

Step-by-step explanation:

The midpoint (M) between two given points is the average of their coordinate values:

M = (A + B)/2 = ((-8, 1) +(5, -2))/2 = (-3, -1)/2

M = (-3/2, -1/2) . . . . . matches choice D

4 0

3 years ago

What is the area of ΔABC? Round to the nearest tenth of a square unit.

Westkost [7]

Draw a perpendicular segment from point C to the midpoint of AB. Using the trig sine function sin 80 = x/6 which gives 5.91 for the perpendicular segment. Using the formula A=1/2bh, A= 1/2 x5.91x2sqrt 2 A= 8.4

3 0

4 years ago

Read 2 more answers

Write an equation of the perpendicular bisector of the line segment whose endpoints are (−1,1) and (7,−5)

icang [17]

The equation is $y = \frac{3}{2} x - \frac{11}{2}$

<u>Explanation:</u>

We have to first find the mid-point of the segment, the formula for which is

$(\frac{x_1+x_2}{2} , \frac{y_1+y_2}{2} )$

So, the midpoint will be $(\frac{-1+7}{2} , \frac{1-5}{2} )\\\\$

= $(3,-2)$

It is the point at which the segment will be bisected.

Since we are finding a perpendicular bisector, we must determine what slope is perpendicular to that of the existing segment. To determine the segment's slope, we use the slope formula $\frac{y_2-y_1}{x_2-x_1}$