Answer:
-3/5
Step-by-step explanation:
First represent this with numbers. Less means subtraction -, times means multiplication *, is means equals =.
And let's represent "a number" with x.
63 - 15x = 72
Solve for x. First subtract 63 from both sides.
-15x = 72-63
-15x = 9
x = -9/15 = <u>-3/5</u>
Answer:
9^5
Step-by-step explanation:
the number you're multiplying stays the same and you add your powers I believe.
so it's basically 9•1 and the ^2+^3=^5
Just measure the width (or height, if you'll be stacking the pennies
a mile high) of a penny, then divide 5280 feet by whatever you find.
This is a great activity for a class, and in fact a good way to start
the project. First take one penny, and work out an answer. Then get
100 pennies, and measure them; do the same calculation to see how many
pennies it will take to make a mile. There will probably be a
difference, because you can measure 100 pennies more accurately than a
single penny. Or maybe you have a micrometer that will measure one
penny precisely. Which is better can be a good discussion starter. And
don't forget to try it in metric, too.
Just to illustrate, using a very rough estimate of a penny's width,
let's say a penny is about 3/4 inch wide. The number of pennies in a
mile will be
5280 ft 12 in 1 penny
1 mile * ------- * ----- * ------- = 5280 * 12 * 4/3 pennies
1 mi 1 ft 3/4 in
This gives about 84,480 pennies. (This method of doing calculations
with units is very helpful, and would be worth teaching.)
If we measure 100 pennies as 6 ft 1 in, we will get
5280 ft 100 pennies
1 mile * ------- * ----------- = 5280 * 100 * 12 / 73 pennies
1 mi 6 1/12 ft
This gives us 86794.5205 pennies in a mile.
