Example 1 

Translate each sentence into an equation. 

 Twice the sum of three and  

k is the same as twelve. 

the sum of is the 

twice three and  

k same as twelve 

(twice)           (the sum of three and k)           (is the same as)                    (twelve) 

    2 ×                     (3 + k)                                      =                                  12 

The equation is 2(3+k) = 12. 

Example 2 Use the Four-Step Plan 

Jordan’s family is going to take a trip to Paris and visit the Eiffel Tower. The currency for France 

is the Euro which is written with a comma after two digits. The total cost for Jordan and his family 

will be 35,70 Euros. If the cost is 9,90 Euros for adults and 5,30 Euros for children to tour the 

tower, what is the total cost for the children? 

Explore You know that Jordan’s parents cost 9,90 + 9,90 = 19,80 Euros to tour the tower. You know 

that the total cost is 35,70 Euros. You want to find how much the children will cost. 

Plan Write an equation to represent the situation. Let c represent the cost for the children. 

19,80 + c = 35,70 

Solve 19,80 + c = 35,70 Find c mentally by asking, "What number plus 19,80 equals 35,70? 

c = 15,90 

It will cost 15,90 Euros for the children in Jordan’s family to tour the Eiffel Tower. 

Examine If 19,80 Euros is spent on the adults and 15,90 Euros is spent on the children, 

then 19,80 + 15,90 = 35,70 Euros will be spent total. The answer makes sense. 

Translate this sentence into an eqution.

 Fifteen more than z times six is y times two minus eleven.

15+6z=2y-11

Jellybeans

A popular jellybean manufacturer produces 1,250,000 jellybeans per hour. How many hours does it take them to produce 10,000,000 jellybeans?

1,250,000x  =  10,000,000

1,250,000         1,250,000                        x=8 hours