+0

# I Don't Get This and I Really Want to Learn.

0
353
5
+410

This Question Has 2 Parts That Don't Even Match. I Don't Know Why.

Part A:

If two consecutive whole numbers have a different number of digits, then their product must be a multiple of...

4

11

15

100

Part B:

Last month I spent \$24 on magnets that cost 80 cents each, and this monthI spent \$24 on magnets that cost \$1.20 each. The average cost per magnet was...

92 cents

96 cents

\$1

\$1.04

Thanks for your time and help!

Jan 24, 2019

#1
+26007
0

9 x 10 = 90    divisible by  15

99 x 100 = 9900    divisible by 4 and 15

999 x 1000 = 999 000  divisible by 4 and 15      see a pattern here?

B:  2400 cents /80 cents/magnet  = 30 magnets     2400/120 = 20 magnets

4800 total / (30 + 20 magnets) = 96 cents/magnet

Jan 24, 2019
edited by ElectricPavlov  Jan 25, 2019
#2
+6196
+1

90 is divisible by 4?

Rom  Jan 25, 2019
#3
+1

There might be some magnetic interference. You know, from all the magnets in the other question ... LOL

Guest Jan 25, 2019
#4
+26007
0

Well yah......22.5           it's just not a 'factor'          ooops....fixed..

.Miscopied from my scratch pad....

ElectricPavlov  Jan 25, 2019
edited by ElectricPavlov  Jan 25, 2019
#5
+770
+2

No, the factor that is in all the products is 15, which is why it is highlighted.

PartialMathematician  Jan 25, 2019