Answer:
6 weeks
S/17=T/9=k
S=17k
T=9k, k=T/9
S=13+3.5*w
T=3*w
13+3.5w=17*3w/9
13+3.5w=51w/9
*9 *9
117+31.5w=51w
-31.5w -31.5w
117=19.5w
w=117/19.5
w=6
Explanation:
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