Lingling's height is 1.42 meters. Standing on a 0.4-meter-high stool, she is 0.15 meters taller than her mother. How many meters is her mother's height?
玲玲的身高是1.42米，她站在0.4米高的凳子上比妈妈高0.15米，妈妈的身高是多少米？
<gadget id="calculator">0.4 - 0.15</gadget>
<output>0.25</output>

<gadget id="calculator">1.42 + 0.25</gadget>
<output>1.67</output>

<result>1.67</result>