"We need to ensure that not only the over-60s are considered but also younger people," she told German TV.
She also defended "painful" concessions made to the centre-left Social Democrats (SPD) to clinch a coalition deal.
The deal followed months of wrangling after an inconclusive election.
However, it still needs to be approved by the SPD's 460,000 members, with the result due in March.
On Friday SPD leader Martin Schulz abandoned a plan to serve as foreign minister in the new government, saying he did not want a debate about his role to jeopardise the new coalition.
"Now we need to show that we can start with a new team," Mrs Merkel said. The CDU has six ministerial posts to fill.Some in her conservative CDU/CSU party are unhappy that the key finance ministry has gone to the SPD, fearing that the fiscal discipline of former Finance Minister Wolfgang Schäuble could become a thing of the past.
But Mrs Merkel sought to reassure her critics.
"I want to say that the we have also approved the policies and the finance minister cannot simply do as he likes," she said.
The SPD have been critical of what they call the "forced austerity" imposed on struggling southern European countries such as Greece under Mr Schäuble and said during the election campaign that they would boost investment.
On Saturday the SPD's Olaf Scholz, who is expected to become finance minister, said Germany should not tell other European countries how to run their economies and that mistakes had been made.
But Mr Scholz also said that the SPD would maintain Mr Schäuble's balanced budget policy.
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