Keywords for Multiplication

Keywords for Multiplication exercise

• Find the right ways to express multiplication.

  Hints

  The keyword factor indicates multiplication.

  There exist different ways of writing down a product.

  Regardless of how a product is written down, the result is always the same. The result of multiplication is the product.

  Solution

  First of all we need to decide which operation we have to use.

  The body weight of Kong is $350$ lbs. A strength factor of $10$ is given too.

  The keyword factor indicates, that we have to multiply.

  Here you see different ways to write a multiplication down. Regardless of how it is written down, the result, a product, is always the same:

  • $350 \times 10 =3500$
  • $350(10)=3500$
  • $3500\cdot 10=3500$

• Find the keywords indicating multiplication.

  Hints

  Here you see some keywords for multiplication:

  • product
  • as many as
  • doubled ($\times 2$)
  • tripled ($\times 3$)

  Here you see different ways to write down multiplication.

  Read $\times$ as times.

  Solution

  Griff registers a strength factor of $4$.

  We can also say times $4$ or quadruple.

  All of those keyword indicate multiplication.

  This leads to $25\times 4=10$.

• Find the right expression.

  Hints

  Decide the keywords and the operation they indicate.

  Here you get some keywords for multiplication

  • times
  • product
  • as many as
  • double ($\times 2$)
  • triple ($\times 3$)

  Decide what to multiply.

  Let's have a look at an example: Paul is buying $5$ muffins, at $2$ dollars per muffin.

  So he has to pay $5\times 2=10$ dollars in total.

  Solution

  The elephant is able to carry $2.5$ lbs. for each $1$ lb. of its own body weight.

  He weights $12000$ lbs. So we can find the carry weight as follows:

  $12000\times 2.5=30000$ lbs.

  His friend the tiger has a strength factor of $3$, a triple, and a body of weight of $400$ lbs.

  Again we have to multiply the values, $400\times 3=1200$, to get the carry weight of $1200$ lbs.

• Identify the correct expression.

  Hints

  You need two pieces of cake for each of your friends.

  How many pieces of cake do you need for $4$ friends?

  Right: You have to multiply $4\times 2=8$ to get the number of needed pieces of cake.

  $7$ days are one week.

  Cooking or baking are good examples for multiplying:

  If you know the recipe for $10$ muffins, you have to multiply the amounts of ingredients accordingly.

  • For $25$ muffins you have to multiply by $2.5$.
  • For $40$ muffins you have to multiply by $4$.

  Solution

  • Sally's buying of chairs

  The keyword is each: so she must multiply $12\times 15=180$. She has to pay $180$ dollars in total.

  $~$

  • Biking Paul

  The measure miles per hour includes the keyword per for multiplication. So we conclude the resulting miles as follows:

  $13 \frac{\text{miles}}{\text{hour}}\times 10 \text{ hours}= 130$ miles. Here you can shorten the fraction by hour.

  $~$

  • Swimming Matteo

  Every week indicates multiplication. Let's do the math: $7\times 20=140$. That's the desired number of laps.

  $~$

  • Apple pie

  $11$ apples per pie and $7$ pies lead to $11\cdot 7=77$ apples in total for $7$ pies.

• Determine the keywords for multiplication.

  Hints

  Remember for addition: summand plus summand equal sum.

  Imagine a word problem with the corresponding keyword.

  Let's have a look at the following example: the amount of $20$ dollars Paul saved is tripled by his aunt Sally.

  The corresponding expression is given by $3\times 20$.

  Keep the following for subtraction in mind: minuend minus subtrahend equal difference.

  Solution

  Here you see some keywords indicating multiplication:

  • times
  • quadruple
  • for every
  • double
  • per

  We say that

  multiplicator $\times$ multiplicand $=$ product

  or

  factor $\times$ factor $=$ product.

  All these terms are keywords for multiplication too.

• Determine the strength factor.

  Hints

  Each strength factor is a decimal number less than $1$.

  If you know the strength factor you have to multiply by, then multiply it by the body weight to get the amount of ice cream eaten.

  Turn the equation,

  strength factor $\times$ weight $=$ amount of ice cream,

  into a division.

  Let's have a look at the following example: we know the carry weight of the elephant, i.e. $30000$ lbs, and his body weight of $15000$ lbs. We get the strength factor as follows:

  $f=\frac{30000}{15000}=2$.

  Solution

  Here we know the body weight for each person as well as Billy the cat. We also know the amount of ice cream each family member eats.

  How can we determine the strength factor for each person as well as for Billy?

  We divide the amount of ice cream by the bodyweight.

  Father

  $f=\frac{1.26}{180}=0.007$

  Mother

  $f=\frac{0.56}{140}=0.004$

  Paul

  $f=\frac{0.56}{70}=0.008$

  Billy

  $f=\frac{0.75}{15}=0.05$