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\begin{aligned} &\int_{1.5}^{2.7} \operatorname{INT}(x) \mathrm{dx}=(\text { area for } x \text { between } 1.5 \text { and } 2)+(\text { area for } x \text { between } 2 \text { and 2.7) } \\ &=(\text { base })(\text { height })+(\text { base })(\text { height })=(.5)(1)+(.7)(2)=1.9 \end{aligned}