Knowledge and Understanding

Explain why the solution to 2/5 x +3=1/2 is equivalent to the solution of 4x + 30 = 5

equation 1             equation 2
2/5 = 0.4                4
+3                          +30
1/2=0.5                  =5



equation 2 is equivalent to equation 1 because all the numbers for equation 2 are up one place value
the answer will always be the same throughout place values

x= -6.25

40x + 300 = 50 is equivalent to the other equations

                                  

Textbook Pg. 62 #25

25. create a word problem that involves operations with rational numbers in decimal form. Make sure you can solve your problem. Then, have a classmate solve your problem

If 3 pizzas were cut into 8.5 slices per pizza then 2.145 slices were eaten but 0.503 of a slice was left over with 2 extra pizzas that was ordered recently, how many pizza slices are there left?







Answer:  3*8.5-2.145+0.503+8.5*2 = 25.5-2.145+0.503+17
                                                         = 40.858


There would be 40.858 slices of pizza left