Multiplication & Division Flashcards
Look at the set of numbers below.
1, 4, 2, 1, 4, 2, 1, 4, 2, 1, 4 …
(a) What is the 26th number?
(b) What is the total sum of the first 15 numbers?
- 1, 4, 2 (3 numbers) repeat.
- Which number close to but less than 26 is divisible by 3? 24/3 = 8. We have 8 full groups of 1, 4, 2
- To identify the 26th number, we must calculate how many numbers go after 24. 26-24=2. The second number in the pattern is 4.
- We need to sum up the first 15 numbers.
- For this we must identify which numbers these are. 15 is divisible by 3, which means we sum up 5 groups of 1, 4, 2.
- 1+4+2=7. 7*5=35.
Divide 20 ice-cream cones into groups of 4
Divide 20 ice-cream cones equally among 4 people
There are 5 ice-cream cones in each of 4 groups.
Each of 4 persons gets 5 ice-cream scones.
This year, Sierra and her aunt have a total age of 80. Her aunt is 4 times as old as Sierra.
(a) How old is Sierra now?
(b) How old is her aunt now?
a) A = 4S
b) A total age is 4S + S = 5S (5 equal parts)
c) S = 16
d) A = 64
Maria scored a total of 171 points in English and math. She scored twice as many points in English as she did in math. How many points did she score in English?
a) E=2M. Math’s score is 1/2 of the English’s score or M=1/2E
b) Because M is exactly half of E, we have 3 equal parts.
C) 171 points divided by 3 results in the score per one part.
D) E is 2/3 of the total 114
The length of the rectangle is twice its width.
l=2w
3w in total
