Question

Translate the words into a mathematical expression. Two-thirds of the sum of 122 and 98. 99 divided by 10, then multiplied by the sum of 84 and 3. Compare the two expressions.

Answer 1

1st expression is
`(2)/(3)(122+98),` because

• the sum of 122 and 98 is 122+98=220;
• Two-thirds of the sum of 122 and 98 is
  `(2)/(3)(122+98)=(440)/(3)=146(2)/(3).`

2nd expression is
`(99)/(10)\cdot (84+3),` because

• the sum of 84 and 3 is 84+3;
• 99 divided by 10 is
  `(99)/(10);`
• 99 divided by 10, then multiplied by the sum of 84 and 3 is
  `(99)/(10)\cdot (84+3)=(99)/(10)\cdot 87=(8,613)/(10)=861.3`

3. If compare these two expressions, then

`(2)/(3)(122+98)<(99)/(10)\cdot (84+3).`