# Math Help - Percent Word Problems

1. ## Percent Word Problems

We are having trouble understanding the procedures for these problems. Todays problem is:
Night came and the mangroves and palmettos closed in on their victim. If 27 percent were mangroves and 511 were palmettos, how many total shrubs were on the attack?

This is the second time we have run across this type of problem. Can you please show us the formula and procedure to complete these?

2. Let $x$ be the total number of shrubs. Since $27\%$ of the total are mangroves, than there are $.27x$ total mangroves. This number added to $511$, which is the number of palmettos, is equal to the total $x$.

$.27x + 511 = x$

$
511 = .73x$

$\frac{{511}}{{.73}} = x$

$700 = x$

On a side note, the total number of mangroves can then be seen to be:

$.27 \times 700 = 189$

or

$700 - 511 = 189$

3. Originally Posted by wrath27
We are having trouble understanding the procedures for these problems. Todays problem is:
Night came and the mangroves and palmettos closed in on their victim. If 27 percent were mangroves and 511 were palmettos, how many total shrubs were on the attack?

This is the second time we have run across this type of problem. Can you please show us the formula and procedure to complete these?
Hey, Wrath

You're given all the information you need in order to work the question out. I've highlighted the key bits.

Hints: (Try to work it out using this)
If 27% of shrubs are mangroves, what percentage are palmettos?
Now if 511 scrubs are just made up by the percentage of palmettos, 100% if scrubs are made up by?

Solution

27% are mangroves means that 73% are palmettos. We know that there are 511 palmettos, so if you call the total number of shrubs on attack $x$ then

$0.73 x = 511$

so x = 700.

4. Thanks to boh of you for posting, this helped a ton!

5. ## Extension of this question

John spends 2/5 of his pocket money on a Football and 1/4 of his pocket money on sweets. If he has $1.75 left, how much pocket money did he have in the beginnning. I got to 25% and 40% respectively of the sum has been spent, leaving a balance of$1.75. However, I couldn't break it down...can anyone help please ?

Nick

Originally Posted by WWTL@WHL
Hey, Wrath

You're given all the information you need in order to work the question out. I've highlighted the key bits.

Hints: (Try to work it out using this)
If 27% of shrubs are mangroves, what percentage are palmettos?
Now if 511 scrubs are just made up by the percentage of palmettos, 100% if scrubs are made up by?

Solution

27% are mangroves means that 73% are palmettos. We know that there are 511 palmettos, so if you call the total number of shrubs on attack $x$ then

$0.73 x = 511$

so x = 700.

6. Originally Posted by wrath27
We are having trouble understanding the procedures for these problems. Todays problem is:
Night came and the mangroves and palmettos closed in on their victim. If 27 percent were mangroves and 511 were palmettos, how many total shrubs were on the attack?

This is the second time we have run across this type of problem. Can you please show us the formula and procedure to complete these?

7. Can someone help me on where to find how to
do a percentage graph????? Getting fustrated!!!
omg..... need help!!!!

8. Originally Posted by nick2009

John spends 2/5 of his pocket money on a Football and 1/4 of his pocket money on sweets. If he has $1.75 left, how much pocket money did he have in the beginnning. I got to 25% and 40% respectively of the sum has been spent, leaving a balance of$1.75. However, I couldn't break it down...can anyone help please ?

Nick
Let $x$ be the amount of money you started out with. Then the amount John spent on the football is $\frac{2}{5}x$ and the amount he spent on the sweets is $\frac{1}{4}x$. He is left with $\1.75$, so your equation is:

$x-\left( \frac{2}{5}x+\frac{1}{4}x \right)=\1.75$. This is because you start with $x$ and you spend $\left( \frac{2}{5}x+\frac{1}{4}x \right)$. Factor out the $x$ to get $
x\left[ {1 - \left( {\frac{2}
{5} + \frac{1}
{4}} \right)} \right] = \ 1.75 \Rightarrow \frac{7}
{{20}}x = \ 1.75 \Rightarrow x = \ 1.75\left( {\frac{{20}}
{7}} \right) = \ 5.00$
.

John started with $\5.00$.