Decimal Points in Products

Warmup

Activity #1

Division or Multiplication by the Reciprocal?

• Below are two sets of problems. First solve the problems labeled A, and then solve the problems labeled B. Then compare your results.

• Use your work in the previous problems to find each of the following. Explain your reasoning.

(1.) 720 · (0.1)

(2.) 720 · (0.01)

• Find each product below. Show your reasoning.

(1.) 36 · (0.1)

(2.) 24.5 · (0.1)

(3.) 1.8 · (0.1)

(4.) 54 · (0.01)

(5.) (9.2) · (0.01)

Activity #2

Multiply two Decimal Numbers.

• Check the numbers 1 through 6 one at a time to see the steps in multiplying decimal numbers.​

• Answer the following questions;

(1) Find the value of each product below by following the six steps outlined in the applet above.

(i.) (0.3) · (0.02)

(ii.) (0.7) · (0.05)

(2.) Calculate the value of each expression below by writing the decimal factors as fractions, then writing their product as a decimal.

(i.) (0.01) · (0.02)

(ii.) (0.3) · (0.2)

(iii.) (1.2) · 5

(iv.) (0.9) · (1.1)

(v.) (1.5) · 2

Activity #3

Multiply a Whole Number by a Decimal.

• Start by checking the box in Step 1​
• Read the statement and check the Show Me box​.
• Continue to check the boxes through Step 3​
• Read through the final statement in green.
• Use the slider to increase the number of decimal places.
• Click to keep practicing.
• Use the slider to increase the number of decimal places.

Challenge #1

Solve the following problems and choose the correct answer.

Challenge #2

Which expression has the same value as (0.06)·(0.154)?

Challenge #3