The laboratory spent 2 / 3 * 150 = 300 / 3 = $<<2/3*150=100>>100 on test tubes.
They spent a further 100 / 2 = $<<100/2=50>>50 on safety gear.
In all, they spent 150 + 100 + 50 = $<<150+100+50=300>>300.
Thus, 325 - 300 = $<<325-300=25>>25 of the laboratory’s budget remained.
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