Problem: Wwo sentences:
Two officials initially said about 300 workers had been arrested at 61 stores in 21 states .
But the officials later revised the numbers and said about 250 had been arrested at some 60 stores .
Do they have the same meaning?

Answer: yes

Problem: Wwo sentences:
A positive PSA test has to be followed up with a biopsy or other procedures before cancer can be confirmed .
Before confirming a diagnosis of cancer , a positive PSA test must be followed up with a biopsy or other procedures .
Do they have the same meaning?

Answer: yes

Problem: Wwo sentences:
" I can tell you that it 's routine for IBM to challenge its internal IT teams to rigorously test new platforms and technologies inside IBM . "
" It is routine for IBM to challenge its internal IT team to rigorously test new platforms and technology inside IBM . "
Do they have the same meaning?

Answer: yes

Problem: Wwo sentences:
They returned in 1999 after rebel raids on a neighboring Russian region and a series of deadly apartment-building bombings that were blamed on the rebels .
In 1999 , troops returned after rebel raids on a neighbouring Russian region and a series of deadly apartment-house bombings in Russian cities that were blamed on the rebels .
Do they have the same meaning?

Answer:
yes