9514 1404 393
Answer:
Step-by-step explanation:
The difference in mass of the bars is 19-15 = 4 kg. The difference in mass of the added weight is 6-2 = 4 kg. The difference in total mass (bar +added) is reduced by the difference in added mass after each set. The number of sets required to reduce the difference to zero is ...
(4 kg)/(4 kg/set) = 1 set
After 1 set, Hunter will increase the mass to 19 kg + 2 kg = 21 kg.
After 1 set, his partner will increase the mass to 15 kg +6 kg = 21 kg.
Both will be lifting 21 kg for their 2nd set, after they have completed 1 set.
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<em>Additional comment</em>
You can write equations for the mass being lifted by Hunter (h) and his partner (p) after s sets:
h = 19 +2s
p = 15 +6s
The masses will be equal when ...
h = p
19 +2s = 15 +6s
19 = 15 +4s . . . . . . . subtract 2s
4 = 4s . . . . . . . . . . . subtract 15
Note that the number on the left side of the equation is 19-15, the difference of bar masses. The coefficient on the right side is 6-2, the difference in the added masses. To find the number of sets (s), we divide the equation by the coefficient of s:
4/4 = s = 1
In the above solution we skipped directly to this final division in order to find the number of sets until the lifted masses were equal.
