The supply curve slopes upwards from left to right because price and quantity supplied usually move in the same direction.

• When the price rises, sellers can earn more profit.
• They try to produce and sell more goods.
• More firms may enter the market to earn profit.

Example: If the price of pens rises, a shopkeeper may offer more pens for sale.

Conclusion: Higher price usually leads to higher quantity supplied, when other factors remain constant.