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Hi Karen. Let D equal Dave's age, H equal Henry's age, and T equal Tim's age. Now translate the sentences into equations: "Henry is 17 years younger than 3 times Dave's age": H = 3D  17 "Tim is 17 years older than twice Henry's age": T = 2H + 17 "Dave is 7 years younger than his brother (Henry)": D = H  7 "How many candles are on Dave's birthday cake?": Find D. So solve for D using the elimination and/or the substitution method for simultaneous equations to find D: You can look up those concepts in our Quick Search if you need more help. Cheers,  


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