Question 1045491
Let n be the initial speed. Then:
240/n+192/(n+8)=10
240(n+8)+192n=10(n²+8n)
432n+1920=10n²+80n
10n²-352n-1920=0
5n²-176n-960=0
(5n+24)(n-40)=0
n=40,-24/5
Throwing out the negative result, we get 40 kph as the original speed. &#9786;&#9786;&#9786;&#9786;