The most deadly attack was a car bombing that killed at least two people in Sadr City, a mainly Shia area of Baghdad, on Thursday morning.
The explosion tore through a crowded market and wounded as many as 26 people, Iraq police said. Some reports put the toll at seven.
Other bomb attacks killed two people in the town of Daquq 45km (25 miles) south of Kirkuk and wounded several in Sinjar, west of Mosul, and in Mahmudiya, south of Baghdad.
Killings in Baquba
Another six people were killed in a string of shootings in and around Baquba, a religiously mixed town north of the capital, police said.
Three of the dead were brothers, who owned an agricultural equipment shop, while another was a salesman. The four were shot in the centre of Baquba market.
A fifth man was shot by men who stole his car outside Baquba, while a civilian from the village of Zhagania, north of the town, was shot dead in a coffee shop, police said.
In the town of Muqdadiya, northeast of Baquba, 20 people were wounded including three policemen when three mortar rounds hit a market on Thursday, police said.
Six mutilated bodies were also pulled out of the Tigris river near the village of Suwayra, south of Baghdad. Government employees were also killed in Kirkuk and Falluja.
Iraq PM: Iraqis ready to take over
Iraqi government forces are ready to take charge of security in most of the country and would be able to cope if foreign, US-led forces pulled out, Nuri al-Maliki, Iraq's prime minister, reportedly said on Thursday.
"Iraqi forces are now capable of taking charge of security tasks in most of Iraq's provinces and would be able to fill the vacuum if multinational forces withdrew," he said, after receiving Robert Fico, his Slovak counterpart, AFP reported.
Iraq also said on Thursday that a draft $39 billion budget for 2007 had been delivered to the cabinet for review, prior to final parliamentary approval.
"It has been prepared professionally and in a good way. Unlike the budget of 2006," Ali al-Dabagh, a government spokesman, told a press conference.
The 2007 draft compares with a 2006 budget of $34 billion.