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<!-- EMBER_CLI_FASTBOOT_TITLE -->  <meta name="ember-cli-head-start" content>  <title>Computed Properties and Aggregate Data - The Object Model - Ember Guides</title>

  <meta name="description" content="Sometimes you have a computed property whose value depends on the properties of items in an array. For example, you may have an array of todo items, and want to calculate the incomplet