You're logged in to a Mac as a standard user. How can you display the OS X Yosemite build number?
Choose About This Mac from the Apple menu, then click the OS X version number to reveal the build number.
In the General pane of System Preferences, click the Info disclosure triangle to reveal the build number.
Type build number in Spotlight, then scroll through the results until the build number appears.
Choose Software Update from the Apple menu, then choose Build Number from the Update menu.
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