The price of apples in a fruit shop is (5/2) yuan per kilogram, and the price of bananas is cheaper than apples (7/10). How much cheaper is a banana per kilogram than an apple per kilogram?
某水果店的苹果每千克(5/2)元，香蕉的价钱比苹果便宜(7/10)．每千克香蕉比每千克苹果便宜多少元？
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(5/2) * (7/10)</gadget>
<output>7/4 = around 1.75</output>

<result>7/4 = around 1.75</result>