Holding displacement fixed while layer height changes shows the inverse side of the strain ratio. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
One metre over two gives one half strain
Hold displacement at 1 metre. A layer height of 2 metres gives shear strain 1/2. This is the denominator view of the same strain ratio.
1/2=21
Four metres halves the strain again
With displacement still 1 metre, height 4 metres gives strain 1/4. A taller layer makes the same top shift less severe.
1/4=41
Eight metres lowers the ratio to one eighth
At height 8 metres, the same 1 metre displacement gives strain 1/8. The three rows keep strain below one and show the inverse denominator effect.