คำนวณ รบกวนฟอร์มโจทย์เป็นสมการและหาคำตอบด้วยค่ะ ขอบพระคุณค่ะ

Eva and Ruth earn money by working. Ruth earns $5 an hour. Eva earns $3 an hour more than Ruth.
Ruth works twice as long as Eva. Together they earn a total of $180.
Form and solve an equation to find out how much does Eva earns?
Thank you for all helping me.