title: Add A1 to C1 if B1 = Specific Number
body: <p>I will try to be as clear and concise as possible. I am working on a spreadsheet in which I have item prices listed in a range of A1:A40. B1:B40 lists a numerical digit (either 1, 2, 3, etc.) that corresponds with a purchase category type (groceries, gas, etc.). Now I want one cell, such as C1, to add all instances in the A range that equal a specific number in B.</p>
  
  <p>For example:</p>
  
  <pre><code> A1 = $5.00 | B1 = 1 | C1 = The sum in range A1:A3 if it's corresponding B value is equal to 1 (In this case B1 and B3, so C1=A1+A3)
   A2 = $2.50 | B2 = 2 | C2 = The sum in range A1:A3 if it's corresponding B value is equal to 2 (In this case B2, so C2= B2)
   A3 = $4.00 | B3 = 1 | C3 =
  </code></pre>