function fraction_facts_check()
{
	var str1 = document.forms[0].elements[0].value;
	var str2 = document.forms[0].elements[1].value;

	if( str1 == "14" && str2 == "24" )
	{
		helpWin = window.open( "correct1.html", "", "height=300,width=450");
	} 
	else
	{
		if( str1 == "7" && str2 == "12" )
		{
			alert("Yes, that is correct, but I didn't want the simpified fraction.");
		}
		else
		{
			alert("No, that is incorrect.");
		}
	}

	return false;
}

function fraction_facts3_check1()
{
	var str = document.forms[0].elements[0].value;

	if(str == "4" || str == "4/5")
	{
		alert("Correct!");
	}
	else
	{
		if(confirm("Nope, that's not right.  Click \"Ok\" for some help, or \"Cancel\" to try again on your own."))
		{
			window.open("help_ff3.html", "", "height=300,width=450");
		}
	}
}

function fraction_facts3_check2()
{
	var str = document.forms[0].elements[2].value;
	
	if( str == "10" || str == "10/3" )
	{
		alert("Correct!");
	}
	else
	{
		alert("Nope, that is not correct.");
	}
}

function equivalent_check()
{
	var docFormElts=document.forms[0].elements;
	if(docFormElts[0].options[0].selected
	&& docFormElts[1].options[1].selected
	&& docFormElts[2].options[1].selected
	&& docFormElts[3].options[2].selected
	&& docFormElts[4].options[2].selected
	&& docFormElts[5].options[2].selected
	&& docFormElts[6].options[1].selected
	&& docFormElts[7].options[0].selected )
	{
		alert("Correct! All gems were delivered correctly");
	}
	else
	{
		alert("Some gems were sent to the wrong places!");
	}
	return false;
}

function wrench_check()
{
	var docFormElts=document.forms[0].elements;
	if(docFormElts[0].options[4].selected
	&& docFormElts[1].options[7].selected
	&& docFormElts[2].options[0].selected
	&& docFormElts[3].options[1].selected
	&& docFormElts[4].options[2].selected
	&& docFormElts[5].options[3].selected
	&& docFormElts[6].options[6].selected
	&& docFormElts[7].options[5].selected )
	{
		alert("Correct!");
	}
	else
	{
		alert("As you stand back and look at the wrenches, you realize that some are not in order.");
	}
	return false;
}

function parts_check()
{
	if(document.forms[0].elements[0].value == "6 2/3")
	{
		alert("Correct!");
	}
	else
	{
		alert("Incorrect.");
	}
	return false;
}

function bigeyes_check()
{
	//Add help page here.
	if(document.forms[0].elements[0].value == 20)
	{
		alert("Correct");
	}
	else
	{
		alert("Incorrect");
	}
	return false;
}

function bananas_check()
{
	//Add help page here, too.
	if(eval(document.forms[0].elements[0].value) == 1)
	{
		alert("Correct.");
	}
	else
	{
		alert("Incorrect.");
	}
	return false;
}

function add_sub_frac_check1()
{
	if(document.forms[0].elements[0].value=="3" || document.forms[0].elements[0].value == "3:00" || document.forms[0].elements[0].value == "3:00 p.m." || document.forms[0].elements[0].value == "3:00pm" || document.forms[0].elements[0].value == "3:00 pm")
	{
		alert("Yes, that's a good time to schedule lunch.");
	}
	else
	{
		alert("No, that wouldn't be the best time for them to eat.");
	}
	return false;
}

function add_sub_frac_check2()
{
	if(ParseFraction(document.forms[1].elements[0].value) == 2.5 || document.forms[1].elements[0].value == "2 1/2 hours" )
	{
		alert("Yes, that's correct!");
	}
	else
	{
		if( document.forms[1].elements[0].value.indexOf("2.5") != -1 )
		{
			alert("Yes, that may be correct, but I\'d like to see it as a mixed number, not a decimal.");
		}
		else
		{
			alert("No, I don't think that's right.");
		}
	}
	return false;
}

function add_sub_frac_un_check1()
{
	if( document.forms[0].elements[0].value == "20" || document.forms[0].elements[0].value == "20 days" )
	{
		alert("Correct!");
	}
	else
	{
		alert("Incorrect.");
	}
	return false;
}

function add_sub_frac_un_check2()
{
	if(document.forms[1].elements[0].value == "12 3/8")
	{
		alert("Correct!");
	}
	else
	{
		alert("Incorrect.");
	}
}

function maggiesfarm_genericCheck(formNum, answer, decimalAnswer)
{
	if(document.forms[formNum].elements[0].value.indexOf("bushels") != -1)
	{
		document.forms[formNum].elements[0].value = document.forms[formNum].elements[0].value.substr(0, document.forms[formNum].elements[0].value.length-7);
	}
	if(document.forms[formNum].elements[0].value == answer)
	{
		alert("Correct!");
	}
	else
	{
		if(document.forms[formNum].elements[0].value.indexOf(decimalAnswer) != -1 )
		{
			alert("Yes, that may be correct, but Maggie likes to keep track of bushels in fractions, not decimals.  Please Re-enter the answer as a mixed number.");
		}
		else
		{
			if( IsAFraction( document.forms[formNum].elements[0].value ) )
			{
				if( ParseFraction( document.forms[formNum].elements[0].value ) != decimalAnswer )
				{
					if( ParseFraction( document.forms[formNum].elements[0].value ) < decimalAnswer )
					{
						alert("No, you would have a little more than " + document.forms[formNum].elements[0].value + " bushels left");
					}
					else
					{
						alert("No, you would have a little less than " + document.forms[formNum].elements[0].value + " bushels left");
					}
				}
				else
				{
					alert("Yes, that may be correct, but Maggie likes to keep track of his bushels in simplified fractions.");
				}
			}
			else
			{
				if( document.forms[formNum].elements[0].value.length > 0 )
				{
					alert("No, "+document.forms[formNum].elements[0].value+" is not right.");
				}
				else
				{
					alert("No, that is not correct.");
				}
			}
		}	
	}
	return false;
}


function maggiesfarm_check1()
{
	return maggiesfarm_genericCheck( 0, "10 1/4", 10.25);
}

function maggiesfarm_check2()
{
	return maggiesfarm_genericCheck( 1, "7 7/8", 7.875);
}

function maggiesfarm_check3()
{
	if( IsAFraction(document.forms[2].elements[0].value) && ParseFraction(document.forms[2].elements[0].value) == 4.5 )
	{
		if(document.forms[2].elements[0].value != "3 1/2")
		{
			alert("Ah, that's correct, but I'd like to see a reduced fraction!");
			return false;
		}
		else
		{
			alert("Correct!");
			return false;
		}
	}
	else
	{
		return maggiesfarm_genericCheck( 2, "3 1/2", 3.5);
	}
}

function maggiesfarm_check4()
{
	var str=document.forms[3].elements[0].value;
	if(str.length > 0)
	{
		if(str[0] == "$")
		{
			str = str.substr(1,str.length);
		}
		if(str == "25" || str == "25.00")
		{
			alert("Correct.")
		}
		else
		{
			alert(" Maggie looks at you with a puzzled face.\n\n\"I think there's an error in your addition,\" he says."); 
		}
	}
	else
	{
		alert("How much money have you made selling apples?");
	}
	return false;
}

function mult_frac_check()
{
	var str=document.forms[0].elements[0].value;
	if(str=="1/2" || str == "1 / 2")
	{
		alert("Correct.");
	}
	else
	{
		alert("Nope, that's not quite right.");
	}
	return false;
}

function creep1_check()
{	
	if(parseInt(document.forms[0].elements[0].value) == 690)
	{
		alert("Correct!");
	}
	else
	{
		alert("That's not right.  You better find the right answer before Phyllis and her minions devour YOUR homework!");
	}
	return false;
}
	
function reciprocal_check()
{
	if(document.forms[0].elements[0].value == "67")
	{
		alert("Correct.");
	}
	else
	{
		alert("Incorrect.");
	}
	return false;
}

function division_fractions_check1()
{
	var str=document.forms[0].elements[0].value;
	if(str == "7 9/16" || str == "7 9/16")
	{
		alert("Correct!");
	}
	else
	{
		if(IsAFraction(str))
		{	
			if(ParseFraction(str) == 7.5625)
			{
				alert("That may be correct, but it would help the boys more if you could put it in simple, mixed number format.");
			}
			else
			{
				alert("No, that's not quite right.");
			}
		}
		else
		{
			alert("No: the answer must be in fractional form.");
		}
	}
	return false;
}

function division_fractions_check2()
{
	var str=document.forms[1].elements[0].value;
	if(str == "40" || str=="40 rides")
	{
		alert("Correct!");
	}
	else
	{
		alert("Incorrect.");
	}
	return false;
}

function division_fractions_check3()
{
	if(document.forms[2].elements[0].value == "14")
	{
		alert("Good job!");
	}
	else
	{
		alert("Nope, that's not quite right.");
	}
	return false;
}

//various fraction determination function

function IsAFraction( str )
{
	var isFraction=true;
	if( str.length == 0 )
		return false;

	for( var i = 0; i < str.length; i ++ )
	{
		if( !IsValidChar(str[i]) )
		{
			isFraction = false;
		}
	}
	return isFraction;
}

function IsValidChar( ch )
{
	return ( ch == 0 || ch == 1 || ch == 2 || ch == 3 || ch ==4 || ch ==5 || ch ==6 || ch ==7 || ch ==8 || ch ==9 || ch ==" " || ch =="/" );
}

function ParseFraction( frac )
{
	var toReturn;
	var i;
	for( i=0; (i < frac.length) && (frac[i] != " "); i++ );
	
	toReturn =  eval (frac.substr(0, i));
	
	if(i < (frac.length - 1) ) 
	{
		toReturn += eval (frac.substr(i+1, frac.length));
	}
	
	return toReturn;
}