Subtraction question

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Hi i need to Echo out this statement,

Starting weight is: 180 Starting body fat is: 15%
After losing 1 pounds of fat Weight is now 179 body fat is now: 14.53%
After losing 2 pounds of fat Weight is now 178 body fat is now: 14.04%
After losing 3 pounds of fat Weight is now 177 body fat is now: 13.56%
After losing 4 pounds of fat Weight is now 176 body fat is now: 13.07%
After losing 5 pounds of fat Weight is now 175 body fat is now: 12.57%
After losing 6 pounds of fat Weight is now 174 body fat is now: 12.07%

So this is what I have, im not sure how to subtract 1 pound to output 179 and so forth, any help and advice would be appreciated.

Thank you.

<?php

\$start_weight = 180;
\$start_body_fat = 27;
\$start_body_fat_percent = \$start_body_fat/\$start_weight * 100;
\$pounds_lost = 15;
\$first_number= 1;

echo "Starting weight is: ".\$start_weight." Starting body fat is: ".\$start_body_fat_percent."%";
echo "<br>";
echo "After losing 1 pounds of fat weight is now: "\$start_weight"- ".\$first_number." Starting body fat is: ".\$start_body_fat_percent."%";

?>

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You'll want to use a for loop. The code for the loop will be like

```for(\$i = 1; \$i <= \$pounds_lost; \$i++)
{
// work out new body weight, take \$i from \$body_weight
// recalculate body fat percentage, take \$i from \$start_body_fat and divide by new body weight and times by 100
// output how many pounds lost (\$i), new weight and body fat percentage
}
```
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so would it be like this?

<?php

\$start_weight = 180;
\$start_body_fat = 27;
\$start_body_fat_percent = \$start_body_fat/\$start_weight * 100;
\$pounds_lost = 15;

echo "Starting weight is: ".\$start_weight." Starting body fat is: ".\$start_body_fat_percent."%";
for (\$i =1; <= \$pounds_lost; \$i++);

{
echo "After losing 1 pounds of fat weight is now: \$number1" ; echo " & Starting body fat is: ".\$start_body_fat_percent1."%";

}
?>

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Not quite, the loop needs to recalculate the weight and body fat on each iteration.

```for(\$i = 1; \$i <= \$pounds_lost; \$i++)
{
//work out new body weight, take \$i from \$body_weight
\$new_weight = calculate new weight here;

//recalculate body fat percentage, take \$i from \$start_body_fat and divide by new body weight and times by 100
\$new_body_fat_percent = calculate new body fat percent here;

// output how many pounds lost (\$i), new weight and body fat percentage
echo "After losing \$i pounds of fat weight is now: \$new_weight, body fat is: \$new_body_fat_percent%";
}```

On each iteration of the loop you're giving new values to \$new_weight and \$new_body_fat_percent. The output from the loop will then look like

After losing 1 pounds of fat Weight is now 179 body fat is now: 14.53%

After losing 2 pounds of fat Weight is now 178 body fat is now: 14.04%
After losing 3 pounds of fat Weight is now 177 body fat is now: 13.56%
After losing 4 pounds of fat Weight is now 176 body fat is now: 13.07%
After losing 5 pounds of fat Weight is now 175 body fat is now: 12.57%
After losing 6 pounds of fat Weight is now 174 body fat is now: 12.07%
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\$new_weight =\$number1= \$start_weight-1;

??

will that be the new weight?

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Do you know what for loop do? have you read http://php.net/for yet? Learn how the for loop works then try again.

I have told you what you need to do to calculate the new weight and body fat. Loook at the lines that start with // in the code I posted.

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Do you know what for loop do? have you read http://php.net/for yet? Learn how the for loop works then try again.

I have told you what you need to do to calculate the new weight and body fat. Loook at the lines that start with // in the code I posted.

<?php

\$start_weight = 180;

\$start_body_fat = 27;

\$start_body_fat_percent = \$start_body_fat/\$start_weight * 100;

\$pounds_lost = 15;

echo "Starting weight is: ".\$start_weight." Starting body fat is: ".\$start_body_fat_percent."%";

for(\$i = 1; \$i <= \$pounds_lost; \$i++)

{

//work out new body weight, take \$i from \$body_weight*/

\$new_weight = \$i-\$pounds_lost

//recalculate body fat percentage, take \$i from \$start_body_fat and divide by new body weight and times by 100

\$new_body_fat_percent = \$i-\$start_body_fat/\$new_weight *100;

// output how many pounds lost (\$i), new weight and body fat percentage

echo "After losing \$i pounds of fat weight is now: \$new_weight, body fat is: \$new_body_fat_percent%";

}

?>

I have a sytax on the red line, I kno what for loop does, but this is my first example. Im sorry

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This line

```\$new_weight = \$i-\$pounds_lost
```

Is causing the error. It should have a semi-colon (the ; character) at the end of the line. Also \$i-\$pounds_lost should be \$i-\$start_weight

Your on the right path now.

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Im receiving a syntax error on this line

echo "After losing \$i pounds of fat weight is now: \$new_weight, body fat is: \$new_body_fat_percent%";

,

can you atleast show me how to print the first statement

After losing 1 pounds of fat Weight is now 179 body fat is now: 14.53%
After losing 2 pounds of fat Weight is now 178 body fat is now: 14.04%

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Fixed code.

```<?php

\$start_weight = 180;
\$start_body_fat = 27;
\$start_body_fat_percent = \$start_body_fat/\$start_weight * 100;
\$pounds_lost = 15;

echo "Starting weight is: ".\$start_weight." Starting body fat is: ".\$start_body_fat_percent."%<br />";
for(\$i = 1; \$i <= \$pounds_lost; \$i++)
{
//work out new body weight, take \$i from \$body_weight*/
\$new_weight = \$start_weight - \$i;

//recalculate body fat percentage, take \$i from \$start_body_fat and divide by new body weight and times by 100
\$new_body_fat_percent = (\$start_body_fat - \$i)/\$new_weight *100;

// clean up \$new_body_fat_percent;
\$new_body_fat_percent = number_format(\$new_body_fat_percent, 2, '.', ',');

// output how many pounds lost (\$i), new weight and body fat percentage
echo "After losing \$i pounds of fat weight is now: \$new_weight, body fat is: \$new_body_fat_percent%<br />";
}

?>```
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GOT IT

<?php
\$start_weight = 180;
\$start_body_fat = 27;
\$start_body_fat_percent = \$start_body_fat/\$start_weight * 100;
\$pounds_lost = 15;

echo "Starting weight is: ".\$start_weight." Starting body fat is: ".\$start_body_fat_percent."%";

for(\$i = 1; \$i <= \$pounds_lost; \$i++)
{
//work out new body weight, take \$i from \$body_weight
\$new_weight = \$start_weight - \$i;

//new body fat percentage, take \$i from \$start_body_fat and divide by new body weight
\$new_body_fat_percent = ((\$start_body_fat - \$i) / \$new_weight) * 100;

// new weight and body fat percentage
echo "<br/>After losing \$i pounds of fat weight is now: \$new_weight, body fat is: \$new_body_fat_percent%";
}
?>

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