Find the number if $1%$1% of the number is $20$20.
Find the number if $2%$2% of the number is $8$8.
Find the number if $10%$10% of the number is $5$5.
Find the number if $20%$20% of the number is $10$10.
apply percentage increases and decreases in situations; for example, mark-ups, discounts and GST