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13 items are filed under this topic.
Double the number of pennies each week 2019-02-28
From Donald:
If I save a penny a week,double it every week,How many weeks will it take to reach 1,000,000 dollars
Answered by Penny Nom.
Doubling the area of a pamphlet 2015-10-31
From Mariam:
A pamphlet has the following dimensions: 4 cm by 6 cm If the area of the pamphlet is doubled, what will be the length of each side if sides can be integer values only?
Answered by Penny Nom.
Doubling the dimensions of a cone 2014-11-21
From Hannah:
If the volume of a cone of height 10 cm is 261.8 cm3, show that this volume is increased by a factor of 8 if the dimensions of the cone are doubled.
Answered by Penny Nom.
Two problems 2010-04-13
From Dorothy:
1. Explain why the number 123, 456, 789, 101, 112 cannot be a perfect square. (Hint: What is the units digit?)

2. A substance doubles in volume every minute. At 9:00A.M., a small amount is placed in a container. At 10:00A.M., the container is just full. At what time was the container one-eighth full?

Answered by Robert Dawson.
A cube with twice the volume 2010-04-11
From Woojin:
From a given cube create another cube with twice the volume. the cube: 5cm each.
Answered by Tyler Wood.
How much will i have saved in that year? 2009-12-18
From Loretto:
If i save a penny and it doubles every day for one year how much will i have saved in that year
Answered by Robert Dawson.
A number that ends with 2 2008-06-23
From Jim:
A number ends in 2. If you were to place that digit at the beginning of the number, the resulting number will be twice the original. Find the smallest such number.
Answered by Stephen La Rocque.
Doubling every day 2007-10-07
From Jerrie:
Patti saved pennies for 10 days. The first day she saved 1 cent. Every day after that she saved twice as much as the day before. How much money did Patti save altogether?
Answered by Stephen La Rocque.
Doubling time 2005-03-12
From Nick:
Looking for the equation to how many years it will take to double the population given the growth rate is 7%.
Answered by Penny Nom.
33 3/4 doubled 2004-05-22
From A tailor:
need to know how to add 33 3/4 doubled. How do I come up with the solution? I need to know for measuring garments. Usually I measure on the half meaning on the front of the garment and then double it with the measuring tape but I always get stuck when I need to measure 3/4 such as 66 3/4 doubled and etc. Can you help me figure this out easily.
Answered by Penny Nom.
Doubling the size of an object 2003-04-01
From Dave:
If I have a known surface area and volume of an unknown object and I want to double the size of the object, how do I find the new area and volume?
Answered by Walter Whiteley.
7x6 by doubling 2001-01-23
From A student:
Can you think of a way to use doubling to multiply 6x7?
Answered by Allen Herman.
A colony of bacteria 2000-04-22
From Nicci Demmin:
Suppose that the bacteria in a colony can grow unchecked, by the law of exponential change. The colony starts with one bacterium and doubles every half hour. How many bacteria will the colony contain at the end of 50 hours?
Answered by Penny Nom.



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