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Yu-Che Hung
Courses Plus Student 10,607 PointsPHP Basic - Variables in PHP - final challenge task what's wrong with my answer?
They said I multiplied the wrong number.
<?php
//Place your code below this comment
$integerOne =1;
$integerTwo =2;
$integerOne +=5;
$integerTwo -=1;
$floatOne =1.5;
var_dump($integerOne * $floatOne);
?>
3 Answers

Mike Wagner
23,559 PointsPHP has really nasty floating point precision issues as mentioned here and many other places. This often results in weird results in mathematical operations that result from numbers like 1.5 turning into things like 1.4999999[...]
or 1.5000[...]001
internally. In order to solve things like this, it's often necessary to use a function like round()
link, floor()
link, or something else to artificially create the precision necessary to obtain an expected result.

Jonathan Dewitt
8,101 PointsUse echo
instead of var_dump
.

Yu-Che Hung
Courses Plus Student 10,607 Pointsthanks! apprecaite!!