More teeth make you work harder but you also go faster with the same the cadence (chainring revolutions per minute).
More teeth on the rear cog make you go slower.
You need fewer teeth in the front and/or more teeth in the rear when climbing hills.
If you want to go faster without pedaling faster simply shift to a larger chainring in the front or a smaller cog in the rear.
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.