Prime Factors of 60: 2,3, and 5
Prime Factors of 140: 2,5 and 7
All mental math no work needed.
To set the equation,we can first find how much price would be raised within a year:
=500×(1+7%)
=500×1.07
As the years go by the increase would accumulate,and the equation would be:

Hope it helps!
1.QUAD is an isosceles trapezoid 1. Given
2. QD = UA 2. Opposite legs of an isosceles trapezoid are equal
3. QU = QU 3. Reflexive
4. QA = UD 4. Diagonals of an isosceles trapezoid are equal.
5. ΔUAQ = ΔQDU 5. SSS
6. ∠UAQ = ∠QDU 6. CPCTE