Valerie has to send a thank you card to each of 3 people, so she has 3 * 1 = <<3*1=3>>3 thank you cards to mail.
She has 2 bills to mail.
She has 3 more rebates than bills, so 3 + 2 = <<3+2=5>>5 mail-in rebates to mail.
She has twice as many job applications as rebates, so she has 2 * 5 = <<2*5=10>>10 applications to mail.
She has 3 + 2 + 5 + 10 = <<3+2+5+10=20>>20 pieces of mail to send.
The electric bill needs an extra stamp, so she needs 20 + 1 = <<20+1=21>>21 stamps.
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