My parents increased my pocket money by 10% and then three months later increased it by further 10%

my father said this was an increase of 21% can you explain this

What conversions require multiplication

Solve the proportion below 9/81=x/9 x= A. 9 B. 3 C. 1 D. 18

Alaina's sugar cookie recipe calls for 2 1/4 cups of flower. If she wants to make 2/3 a batch of cookies how much flour should she use?

Trevor thinks that left-handed pitchers in a baseball league are more likely to strike out batters than right-handed pitchers are. He's considering each "at-bat" as an opportunity for a strikeout.

Find the Mean, Median, Mode, and Range: 1. 52, 46, 63, 40, 56 2. 40, 24, 7, 37, 43, 16, 24, 25

A newspaper reporter wants to know how popular the hobby of bird watching is in the city. He asked people at the local bird refuge if they watched birds as a hobby. Which of the following best explains whether the reporters data is valid or not?

I am very confused on how to figure out if y = 3/4x is proportional?

Alison wants to buy a mountain bike for $339.12. If she saves $28.26 each month, in how many months will she be able to buy the bike?

At 12 o'clock the temperature was 7°C. The temperature decreased by - 20°C. What is the new temperature?

Ashleys rentals charges $27.50 per hour to rent a surfboard and a wetsuit. Darlas surf shop charges $23.25 per hour to rent a surfboard plus $17 extra for a wetsuit.