document.write( "Question 1122487: Ndiba left the mall and traveled toward the lake. Two hours later Emily left traveling at 70 km/h in an effort to catch up to Ndiba. After traveling for three hours Emily finally caught up. What was Ndiba's average speed.
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Algebra.Com's Answer #738636 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+s+\"$ = Ndiba’s average speed
\n" ); document.write( " $\"+s%2A2+\"$ = distance Ndiba travels before Emily leaves
\n" ); document.write( "Let $\"+d+\"$ = distance Emily travels until they meet
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\n" ); document.write( "Neiba’s equation:
\n" ); document.write( "(1) $\"+d+-+2s+=+s%2A3+\"$
\n" ); document.write( "Emily’s equation:
\n" ); document.write( "(2) $\"+d+=+70%2A3+\"$
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\n" ); document.write( "(1) $\"+d+=+5s+\"$
\n" ); document.write( "And
\n" ); document.write( "(2) $\"+5s+=+70%2A3+\"$
\n" ); document.write( "(2) $\"+s+=+42+\"$
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\n" ); document.write( "Ndiba’s average speed is 42 km/hr
\n" ); document.write( "Check:
\n" ); document.write( "In 1st 2 hrs N traveled $\"+s%2A2+=+84+\"$ km
\n" ); document.write( "In next 3 hrs she traveled $\"+s%2A1+=+126+\"$ km
\n" ); document.write( " $\"+84+%2B+126+=+210+\"$ which was Emily’s distance
\n" ); document.write( "Since $\"+d+=+70%2A3+\"$
\n" ); document.write( "Get 2nd opinion if needed\r
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