=SUMPRODUCT(--(A1:A20="a"),--(B1:B20="rent"),C1:C20)
The double negatives convert TRUE/FALSE of the logic test to 1/0
best wishes
--
Bernard V Liengme
www.stfx.ca/people/bliengme
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"karenm" wrote in message
...
columnA column b column c
c rent a 600
c name a ken
c rent b 200
c name b tom
p rent c 800
p name c bill

i want to sumif (column c) ... if column a is = a AND column b = "rent"