Suppose that with a budget of $200, Deborah spends $120 on sushi and $80 on bagels when sushi costs $5 per piece and bagels cost $5 per bagel. But then, after the price of bagels falls to $4 per bagel, she spends $100 on sushi and $100 on bagels. How many of the extra bagels are due to the substitution effect?

Suppose that with a budget of $200, Deborah spends $120 on sushi and $80 on bagels when sushi costs $5 per piece and bagels cost $5 per bagel. But then, after the price of bagels falls to $4 per bagel, she spends $100 on sushi and $100 on bagels. How many of the extra bagels are due to the substitution effect