CPhill

See if this helps.....

http://smallbusiness.chron.com/shut-firewall-off-macbook-52545.html

(a)/(b) = (4)/(3) , (b)/(d)= (8)/(9) , (c)/(d)= (2)/(5)

then what is (a)/(c)

 From the first ratio, b = (3/4)a             

From the third ratio,  d = (5/2)c      ....so.......

Subbing into the second one

[(3/4)a]  / [(5/2)c]  = 8/9

(3/4) ( 2/5) [a / c]  = 8/9

6/20 [ a / c]  = 8/9

3/10 [a / c]  = 8/9

a/c = 8/9 * 10/3   =  80/27

A = 8000( 1 + .108)^(7 + 5/12)  =  $ 17116.96

The amount accumuated before the change is :

A = 2500(1 + .045 / 12)^(3 * 12)   =  $2860.62

After the change, we have

A =  2860.62 ( 1 + .05/ 4)^(1.5 * 4) = $3081.98

given that a + b = c , a+c=d and b=c+d , where d is a positive integer, what is the gratest value of a ?

Using the first two equations, we have

a + a + b = d →  2a + b = d  

And

d = b - c   → 2a + b = b - c →     2a = -c  →    c = -2a  

b = c - a   →    b = -2a - a   →   b = -3a

b = c + d    →     -3a = -2a + d    →    -a = d   →    a = - d

2x - 3 < x + 2 ≤ 3x + 5    

Let's solve this in pieces

2x - 3 < x + 2      subtract x from both sides ....add 3 to both sides

x  < 5

And

 x + 2 ≤ 3x + 5       subtract x, 5 from both sides

-3 ≤ 2x         divide both sides by  2

-3/2 ≤ x

The solution comes from the intersection of these intervals........this is  [ -3/2, 5 )   or, expressed another way....-3/2 ≤ x < 5

I'm not sure, but saseflower's problem might be that the info on her screen appears to be running off the page.......if she holds down the "Ctrl" key and then hits  the  " - " key next to the   "plus/minus" key on her keyboard, it will reduce her screen size and the dropdown menu may appear.....

I don't see any diagram, but.......if we took a cross section of the cylinder, the longest pencil that could fit  would form the hypotenuse of a right triangle with the other two legs =  8 and 17..........and the length of this hypotenuse =

sqrt [8 ^2 + 17^2]  =  sqrt [353]  = about 18.8 cm

So.....a 19 cm pencil will not fit.....!!!!

sin  = y/ r  = 0.6  = 6/10  

cos  = x / r         and x = sqrt [ r^2  - y^2 ]   =  sqrt [ 10^2 - 6^2 ]  = sqrt [ 100 - 36]  = sqrt[ 64]   = 8

So

cos =  8 / 10  or 0.8

Let his mother's age 6 years ago  = x      and his age then was (1/5)x

And now we know that :

3 times his age now = his mother's age now....so........

3 [ (1/5)x + 6 ] =  x + 6    simplify

(3/5)x + 18 = x + 6     subtract (3/5)x , 6 from both sides

12  = (2/5)x      multiply both sides by 5/2

12 [ 5/2]  = x   = 60/2  = 30

This was his mother's age 6 years ago......so.....she must be 36, now