Hi,

 x nickels, ( x+3 ) dimes, and 2x quarters. 

 5x + 10(x+3) + 25(2x) = 65x + 30

 

Hi,

How much 15% solution and How much 50% solution should be mixed together 

to make 60 gallons of a 30% solution?



      

             

 

Hi,

solve the system using substitution

 

-4x-6y=-12 

-4x -6(5x+19) = -12

-4x -30x - 114 = -12

       -34x = 102

          x = 102/-34

          x = -3   and y = 4

and...

 

Hi,

 velocity = velocity = D/t  (am going to express time in minutes)

 v - w = 715/130 = 5.5

 v + w = 715/110 = 6.5

 2v = 12

  v = 6mi/min  and w = .5mi/min

0r

 v = 360mph and w = 30mph

 

Hi,

How many two-digit counting numbers are not a multiple of 10?

Cannot use 0 in the tens place and not using 0 in the ones place...

 

Or

   two-digit counting numbers minus 9 multiple of tens = 81 

 

Hi,

If there are 450 people surveyed, and 106 people answer "Yes" What is this answer as a percentage P?

 

Hi,

Setting Up algebraically to solve:

sum of two numbersand  is  30

sum of the smaller and 4 times the larger is  78

 x+ y = 30

 x + 4y = 78   || Subtracting 2nd EQ from 1st EQ to eliminate x

    -3y = -48

      y = 16  and x = 14

 

Hi,

Find the slope of the line through the pair of points. 

A(2, –3), 

P(2, 9)  m = (-3-9)/(2-2)  Undefined (CANNOT divide by zero)

this is a vertical line:  x = 2

 

Hi,

[-4, ∞)  x greater than or equal to -4 in interval notation

 

Hi,

The hypothesis test produces a z= -2.60 ⇒ reject Ho

	a	a/2	crtical regions	

80%	0.2	10%	z <-1.28155	          z >+1.28155

90%	0.1	5%	z <-1.645	          z >+1.645

92%	0.8	4%	z <-1.751	          z >+1.751

95%	0.05	2.50%	z <-1.96	          z >+1.96

98%	0.02	1%	z <-2.326	          z >+2.326

99%	0.01	0.50%	z<-2.576	          z >+2.576

 

Hi,

 

Hi,

Line segment AB intersects line segment ED in the middle at the point C

 EC = CD

DC=6+x and CE=2x+1

  2x+ 1 = 6 + x

    x = 5

 

Hi,

What is the multiple zero of 

y=x^2-10x+25

factoring and setting y to ZERO

(x-5)(x-5)= 0

 x = 5 is the multiple zero

 

Hi,

Simplifying

 

Hi,

Suppose the measure of an exterior of an equiangular triangle is (x + 15)°.    What is the value of x?

Measure of an Interior angle of an equiangular triangle is: 60°

The exterior angle (x+15)° is the supplement of the interior angle:

 (x+15)° = 180° - 60° = 120°

   x+15°=120°

     x = 105°



Using Your method of solving:

Perhaps it was because of Your following statement did not say what you wanted it to say.

"Because the 2 angles of a triangle equals the measure of an exterior angle"



better stated would be something like this:

An measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles.

 

Hi,

Find a point-slope form of an equation of the line 

that passes through the point  (-7,9)  and has the slope m=-3

 

Hi,

IF...



  

       4/3 = x

 

Hi,

  | Cross Multiplying to solve

  5(x+7) = 4(x-5)

  5x + 35 = 4x - 20

      x = -55

 

Hi,

   | Cross Multiply to solve for x

 

Hi,

IF...

 

Hi,

IF...

 

Hi,

sally has 12 coins consisting of quarters and dimes.

Question states*** the value adds to $2.25

Translate into an equation: CENTS makes sense

  25x + 10(12-x) = 225¢

       15x = 105¢

          x = 7, number of quarters.  5 Dimes

and...

 

Hi,Re TY

You did not say how You determine the P-value given the z-value

NORMSDIST(.6723) is one such way of doing that ...using an Excel function NORMSDIST.

Chart or TI calculator works as well.

μ = 22  ,  σ =11.9  and z = (30-22)/11.9

P(x>30) = 1 -P(z ≤ .6723) = 1- NORMSDIST(.6723)= 1-.75 = .25 

 

Hi,

4x+6y=15      ||Multiplying 2nd EQ by 4 and adding the EQs to eliminate x

-x+2y=5     

   14y = 35

     y = 35/14 = 5/2   and 

 

Hi,

Find the sale price of a $40.00 shirt at 25% off ...paying 75% or 3/4 of regular price

  = $30

 

Hi,

What is the linear equation f for which 

f(1)=10  

f(2)=20

 

Hi,

three subtracted from a number n.

Expressing algebraically: 

    

 

Hi,



apothem of a regular triangle  is 3, and the base is 4. 

area = (½)(apothem)(perimeter)

area = 

 

Hi,

The plumber worked for 3 times as long as the painter and the painter worked 5 times as long as the electrician's hours  . 

The total wage bill was £630. How much was each man paid? 

Translate into an equation:

Electrician + Painter + Plumber 

 x + 5x + 15x = 21x

 =£630

       

Electrician  = £30 

Painter £150

Plumber £450

 

Hi,

 155 is 25% 'of ' people 

   .25x = 155

      x = 155/.25 = 620, number of  the  people referred to.

   reaching 56 People would be that 9% goal

 

Hi,



Important to Understand z -values as they relate to the Standard Normal curve:

Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  

Note: z = 0 , 50% of the area under the curve is to the left and 50%  to the right



For the normal distribution: 

one  standard deviation from the mean accounts for about 68.2% of the set 

two standard deviations from the mean account for about 95.4% of the set****

and three standard deviations from the mean account for about 99.7%.



μ = 100 ,    σ = 10 

A. 130    > 3 standard deviations from the mean...comparatived to the others listed ... UNUSUAL