The number of peach trees in the orchard is equivalent to (3/5) the number of pear trees and (3/7) the number of apple trees. If there are 260 fewer pear trees than apple trees, how many peach trees are there in the orchard?
果园里桃树的棵数相当于梨树棵数的(3/5)，相当于苹果树棵数的(3/7)．如果梨树比苹果树少260棵，这个果园里桃树有多少棵？
<gadget id="calculator">7 / 3</gadget>
<output>7/3 = around 2.333333</output>

<gadget id="calculator">5 / 3</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">(7/3) - (5/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">260 / (2/3)</gadget>
<output>390</output>

<result>390</result>