Exe. Inverse Proportion

Three people build a wall in 10 days. How long would it take for five people. (Please just key in the number).

A ship has sufficient food to supply 600 passengers for 3 weeks. How long would the food last for 800 people? (answer in 2 decimals place please)

Three men can build a wall in 10 hours. How many men would be needed to build the wall in 7.5 hours?

If it takes 6 men 4 days to dig a hole 3 metres deep, how long will it take 10 men to dig a hole 7 metres deep? (Answer in 1 decimal place please)

A floor is covered by 800 tiles measuring 10 cm2. How many square tiles of side 8cm would be needed to cover the same floor?

A battery has enough energy to operate eight toy bears for 21 hours. For how long could the battery operate 15 toy bears? (Answer in 3 significant figure please)

An engine has enough fuel to operate at full power for 20 minutes. For how long (in minutes) could the engine operate at 35% of full power? (Answer in 3 significant please)

A large drum, when full, contains 260 kg of oil of density 0.9 g/cm3. What mass of petrol, of density 0.84 g/cm3, can be contained in the drum? (Answer in 3 significant figures please)

A wall can be built by 6 men working 8 hours per day in 5 days. How many days will it take 4 men to build the wall if they work only 5 hours per day?

80 machines can produce 4800 identical pens in 5 hours. At this rate, how many pens would 25 machines produce in 7 hours?