document.write( "Question 954263: how many integers between 9 and 99 have an even tens digit and an odd units (ones) digit? \n" ); document.write( "

Algebra.Com's Answer #582826 by MathLover1(20850) $\"\"$ $\"About$

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\n" ); document.write( "First, which numbers between $\"9\"$ and $\"99\"$ have an $\"even\"$ $\"+tens\"$ digit?
\n" ); document.write( "All the $\"20s\"$ , $\"40s\"$ , $\"60s\"$ , and $\"80s\"$ .
\n" ); document.write( "Now just look at the $\"20s\"$ . How many of those have odd units ( $\"ones\"$ ) digits?
\n" ); document.write( "That would be $\"21\"$ , $\"23\"$ , $\"25\"$ , $\"+27\"$ , and $\"29\"$ , which makes $\"five\"$ numbers.
\n" ); document.write( "It is the same for the $\"40s\"$ , $\"60s\"$ , and $\"80s\"$ , so the final answer is:\r
\n" ); document.write( "\n" ); document.write( " $\"5%2A4+=+20\"$ \r
\n" ); document.write( "\n" ); document.write( "there is $\"20\"$ integers between $\"9\"$ and $\"99\"$ that have an even tens digit and an odd units (ones) digit \n" ); document.write( "

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