Dividing by Whole Number Powers of 10
When you divide by a whole number power of ten, does your decimal move to the left, or to the right?
Left! Bonus points if someone can explain why it moves to the left!
Solve! 6.55 ÷ 5
1.31
Solve! 6.3 ÷ 0.7
9
1.8 ÷ 0.05
Do you need to write a zero in the dividend to solve?
YES!
What is a decimal?
A part of a whole
605 ÷ 102
6.05
97.2 ÷ 27
3.6
Solve! 1.52 ÷ 1.9
0.8
Solve! 3.5 ÷ 2.5
1.4
Where might you see a number with a decimal?
prices in stores, measurement, weight, etc.
Rileighann is hiking along a trail that is 13.7 miles long. So far she has hiked along one-tenth of the trail. How far has Rileighann hiked? (Think: to find one tenth of an amount you can split the total into ten equal groups.)
1.37 miles
On Saturday, 12 friends go ice skating. Altogether, they pay $83.40 for admission. They share the cost equally. How much does each person pay?
$6.95
Melanie has a large bag of trail mix that weighs 7.8 pounds. She uses the mix in the large bag to make bags each containing 0.6 pound of mix. How many bags containing 0.6 pound can be made?
13 bags
Alivia has a ribbon that is 2.2 meters long. She cuts the ribbon into 4 equal pieces to trim the edges of her bulletin board. What is the length of each piece of ribbon?
0.55 meters
Does it matter where you place the digits in your quotient? Why or why not?
Yes! You only place digits above numbers that can be divided.
Colin and his sisters caught 100 fish on a weeklong fishing trip. The total weight of the fish was 235 pounds. Write an expression that will find the weight of one fish, and solve. Assume all fish weigh the same amount.
235÷100=2.35 pounds
Matthew cut down a tree that was 28.8 feet tall. Then he cut the tree into 6 equal pieces to take it away. What is the length of each piece?
4.8 feet
Grace bought peppers that cost $0.79 per pound. She paid $3.95 for the peppers. How many pounds of peppers did she buy?
5 Pounds
Ms. Cyr made 23.1 quarts of french onion soup for her students, Mrs. Collins, and Mrs. Cady. She wants to put the same amount of soup into each of the 15 containers.
How much soup should Ms. Cyr put into each container?
1.54 quarts of soup in each container.
What is the very first step when you divide a decimal by another decimal?
Move the decimal in the divisor ( and then in the dividend)
n ÷ 1 02 = 0.123
Find the value of n.
12.3
EJ is sending 8 identical catalogs to one of his friends. If the package with the catalogs weighs 6.72 pounds, how much does each catalog weigh?
0.84 pound
Isabella walked a total of 9.52 miles in a walk-a-thon. If her average speed was 2.8 miles per hour, how long did it take Isabella to complete the walk?
3.4 hours
Who drove the fastest? Select the correct answer.
A Melina drove 369 miles in 6 hours.
B Kiara drove 215 miles in 5 hours.
C Ashleigh drove 500 miles in 8 hours.
D Zoe drove 405 miles in 7 hours.
C; Ashleigh drove the fastest. SLOW DOWN, ASHLEIGH! JEEZ!
Which is greater tenths, thousandths, hundredths?
Tenths!!!