Well, honey, if you want to find a 4-digit number where the digits are reversed when multiplied by 9, the number you're looking for is 1089. That's the only number that plays nice and keeps its digits in line when you multiply it by 9. So, there you have it - 1089 is the magic number you're after.
1
160 degrees.
5 units
none of these are correct
280
bc equals st multiplied by the scale factor.
There are only two single-digit numbers where one is 1/5 of the other. Those are 1 and 5 and they become the outside numbers. From there, it's relatively easy to multiply 5 by 3 to get 15 for the inside numbers.
1
ABCD X 9 = DBCA, If A>1 then there will be the result of 5 digit number. So, A=1 and D=9. B=0, so that the extra from previous digits calculation no carry forward remains. C=8 ABCD = 1089 1089 X 9 = 9801
2178
never
never
No! It equals 4abcd!
27
25 units
38.5
If abcd is a parallelogram, then the lengths ab and ad are sufficient. The perimeter is 36 units.