A constrained ideal Bernoulli budget binds pressure, speed, and height terms. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Speed and pressure trade in the level budget
With density 2, speeds 4 and 6 give kinetic terms 16 and 36 pascals.
84+16=64+36
Height can trade with pressure too
At shared speed 4, heights 1 and 3 make height terms 20 and 60 pascals.
64+16+20=24+16+60
Both ideal budgets close to the same total
Each displayed Bernoulli side totals 100 pascals; hidden losses are outside this model.