Hello All,
I have completed this challenge.

1-For this first you need to create a helper formula field(type-percent) 
Percent Completed :
(DATEVALUE( CreatedDate ) - CloseDate )/100

2- Then you need to create the actual formula field (type- text) by using the helper formula field.
Opportunity Progress :

IF( Percent_Completed__c <=25,"Early", 
IF(Percent_Completed__c <=75,"Middle", 
"Late"))

Thanks,
Nida


 

Sales Managers have asked for an at-a-glance solution to see completeness on leads. Create a helper formula field that looks at 5 key fields on the Lead object and evaluates their completeness, then a second formula field that references the helper formula and returns an image.

>The helper formula field should be on the Lead object with a name of 'Lead Quality Helper' and a resulting API name of 'Lead_Quality_Helper__c'.
>The helper formula should be of type Number.
>The helper formula should evaluate the following 5 fields: Email, Phone, Company, Title, and Industry and return 0 if blank and 1 if not blank. >The formula should then add all the values together to return a total value.
>The image formula should be on the Lead object with a name of 'Lead Quality' and a resulting API name of 'Lead_Quality__c'.
>The image formula should reference the helper formula, and return an image based on the number returned by the helper formula. The helper formula should be of type Text. Note: All of these images are already available in your Developer Edition.

1 = /img/samples/stars_100.gif with alternate text '1 star'
2 = /img/samples/stars_200.gif with alternate text '2 stars'
3 = /img/samples/stars_300.gif with alternate text '3 stars'
4 = /img/samples/stars_400.gif with alternate text '4 stars'
5 = /img/samples/stars_500.gif with alternate text '5 stars'

If none of the fields are filled out, the default should be /img/samples/stars_000.gif with alternate text '0 stars'.
The 'Lead Quality' formula must be added to the Lead Layout page layout.

ok so im having trouble on this challenege on trailhead. im confused what it means by helper formula, like how would we create a helper formular? also how would we create a image formula?

thanks if anyone answers 

The validation rule should be on the Case object.
The validation rule should be named 'Mark_as_Escalated'.
The validation rule should fire if someone tries to set a case as escalated and it is closed, closed when created, or does not have a priority of High.
The validation rule should display the error message 'You can only set a case as escalated if it is high priority and not closed' under the Escalated field when triggered.
Add the 'Escalated' field to the Case page layout.

Your company sells cylindrical hyperbaric chambers. You need a formula field that calculates the volume of a cylinder for you, rounded to the nearest whole number, given its radius and height. Use the existing mathematical formula for the volume of a cylinder, V = πr2h, where r is the radius of the cylinder, h is the height, and π is the constant Pi. Note: Although this formula field might best be created on a custom object, for simplicity, we’ll create this formula on the Opportunity object.
>Create 2 custom fields of type Number on the Opportunity object: ‘radius’ with a resulting API name of ‘radius__c’ and ‘height’ with a resulting API name of ‘height__c’.
>The formula should be named ‘Cylinder Volume’, with the resulting API name ‘Cylinder_Volume__c‘ and should be created on the Opportunity object.
>The formula should reference the custom fields ‘radius__c‘ and ‘height__c‘.
>The formula should use 3.14159 as an approximation of Pi.

Heres the challenge that im stuck on. i have created the 2 custom fields. What im stuck on is where do we create the formula. Do we put it in the custom fields or is there another place u insert it?

thanks if anyone can help
 

Trailhead Module 3:  Create a formula field that determines the number of days between today and the last activity date for a case's account.
Your support team has asked for improved visibility on account activity level at the time they’re helping with customer issues. Specifically, when they’re looking at a case, they’d like to see an at-a-glance view of the number of days since the case’s related account was last active. Create the formula using these requirements.The formula should be on the Case object.
The formula should be of return type Number.
The formula should be named 'Days Since Last Update' and have a resulting API Name of 'Days_Since_Last_Update__c'.
The formula should return the number of days between the account’s Last Activity Date and today.

I created the following:

I created a new custom formula field with return type number and called Days Since Last Update.
I created this formula: Account.LastActivityDate - TODAY()

I get this error message:

Challenge not yet complete... here's what's wrong: 
The 'Days_Since_Last_Update__c' formula field did not return the correct number of days between an Account’s Last Activity Date and today

Can you please assist what I did wrong?  I'm not sure if my formula is even correct with the challenge.  Please help!

Thank you.