# Help with equations

• May 20th 2008, 02:26 PM
Saoirse Mac
Help with equations
Write an equation to help you solve this promblem:
Two-fifthsof my money is €24. How much have I?

Twenty-five per cent of the eggs in a box are broken. If there are three dozen eggs in the box, how many unbroken eggs are there?

The length of a rectangular garden is three times its width. Find the perimeter of the garden if the length is 48m.

Write a story for this equation: 3b + 4 = 10

Thank you
• May 20th 2008, 02:32 PM
Moo
Hello,

Quote:

Originally Posted by Saoirse Mac
Write an equation to help you solve this promblem:
Two-fifthsof my money is €24. How much have I?

Let M be the amount of money you have.

Two-fifths of your money means $M \cdot \frac 25$. What is it equal to ?

Quote:

Twenty-five per cent of the eggs in a box are broken. If there are three dozen eggs in the box, how many unbroken eggs are there?
Let N be the number of unbroken eggs.
There are 3x12=36 eggs in the box.
If 25% of the eggs are broken, this means that 75% are unbroken.

Can you find the equation ?

Quote:

The length of a rectangular garden is three times its width. Find the perimeter of the garden if the length is 48m.
Let W be the width of the garden.
Let L be the length. $L=3W$
The perimeter is defined as : $P=2(L+W)$
And the area as $A=W*L$
• May 20th 2008, 09:37 PM
Jhevon
Quote:

Originally Posted by Saoirse Mac
Write an equation to help you solve this promblem:
Two-fifthsof my money is €24. How much have I?

Let the amount of money you have be x pounds.

then $\frac 25x = 24$

now solve for x

Quote:

Originally Posted by Saoirse Mac

Twenty-five per cent of the eggs in a box are broken. If there are three dozen eggs in the box, how many unbroken eggs are there?

this means 75% of the eggs are unbroken. thus there are 0.75*36 eggs that are not broken. (36 is 3 dozen). just simplify the answer

Quote:

Originally Posted by Saoirse Mac

The length of a rectangular garden is three times its width. Find the perimeter of the garden if the length is 48m.

let the width be x, then the length is 3x.

thus we have 2*width + 2*length = perimeter

i leave it to you to fill plug in the correct things into the equation

Quote:

Originally Posted by Saoirse Mac

Write a story for this equation: 3b + 4 = 10

:p this is stupid. just come up with any ol' thing.

Bob currently has b bobcats. If he gets 4 more than three times the number of bobcats he has now, he will have 10 bob cats. How many bobcats does Bob have?
• May 20th 2008, 10:12 PM
Chris L T521
Quote:

Originally Posted by Saoirse Mac
Write an equation to help you solve this promblem:
Two-fifthsof my money is €24. How much have I?

Twenty-five per cent of the eggs in a box are broken. If there are three dozen eggs in the box, how many unbroken eggs are there?

The length of a rectangular garden is three times its width. Find the perimeter of the garden if the length is 48m.

Write a story for this equation: 3b + 4 = 10

Thank you

#1 $\frac{2}{5}M=24 \implies M=\frac{24 \cdot 5}{2}=60$ euros

#2 $.25x$ are broken, where x is the number of eggs. Thus, if there are 3 dozen = 36 eggs, then $.25(36)=9$ eggs are broken.

#3 Since L=3W, and L=48m, then $W=\frac{48}{3}=16m$. Thus, $P=2L+2W\implies P=2(48m)+2(16m)=96m+32m=128m$.

#4 What kind of story???

Hope this helped you out a little bit! :D
• May 20th 2008, 10:13 PM
Help with equations
Left side = right side
term + term = term + term
-----------------
(2/5) of n = 24
2n/5 = 24
Multiply both sides by 5, then divide both sides by 2.
n = 5(24)/2
n = 60
Is 24 two fifths of 60?
(2/5)60 = 24
Yes, so the answer is correct.
-----------------
There are 3(12)=36 eggs in a box.
25% of the eggs are broken.
How many eggs are not broken?
36 - 0.25(36) = 27
or
100% - 25% = 75%
So unbroken eggs = 0.75(36) = 27
-----------------
L = length, W = width
W = L/3
perimeter P = 2L + 2W for any rectangle.
For this rectangle, thats 2(L + L/3)
Since you already know L = 48, take it from there.
-----------------
A story for 3b + 4 = 10