Video Transcript
Determine, to the nearest tenth, the number of metres in 15 feet.
In order to answer this question, we need to be aware of two conversions. Firstly, that three feet is equal to one yard. We also need to remember the conversion from imperial to metric units of length. One yard is equal to 0.9144 metres.
In this question, we need to convert 15 feet into metres. We will do this in two steps by firstly converting it into yards. Three multiplied by five is equal to 15. This means that we need to multiply one by five to calculate how many yards are equal to 15 feet. One multiplied by five is equal to five. Therefore, five yards is equal to 15 feet.
Our next step is to turn five yards into metres. One multiplied by five is equal to five. This means that we need to multiply 0.9144 by five. We can do this using short column multiplication. It is important when multiplying a decimal by a whole number that we keep the decimal point in the same place.
Five multiplied by four is equal to 20. So, we put a zero in the answer and carry the two. Once again, five multiplied by four is equal to 20. Adding the two that we carried gives us 22. We put a two in the thousandths column and carry a two. Five multiplied by one is equal to five. Adding the two that we carried gives us seven in the hundredths column. Five multiplied by nine is equal to 45. We put a five in the tenths column and carry the four. Finally, five multiplied by zero is equal to zero. Adding the four that we carried gives us four.
As 0.9144 multiplied by five is equal to 4.5720, we can say that five yards is equal to 4.5720 metres. We were asked to give our answer to the nearest tenth. This is the same as saying round to one decimal place, as the tenths column is the first column after the decimal point. Our deciding number will be the number to the right of this, in this case seven. If this number is greater than or equal to five, we round up. Seven is greater than five. Therefore, 4.5720 to the nearest tenth is 4.6. We can therefore say that 15 feet is equal to 4.6 metres to the nearest tenth.
