There are 250 apple trees planted in the school orchard, 120 more than pear trees. How many pear trees are there?
学校果园里栽种的苹果树有250棵，比梨树多120棵．梨树有多少棵？
<gadget id="calculator">250 - 120</gadget>
<output>130</output>

<result>130</result>