Solution (a) :
Total number of parts = 5 + 7 + 8 = 20
Let the sum of the money with them be = x
Cleopatra has =
= 5/20 of x = $17
= 5/20x = 17
= 1/4x = 17
= 1x = 17 × 4 ( transposing ÷4 from LHS to RHS changes ÷4 to ×4 )
= x = 68
Therefore , they have $68 in total .
Solution (b) :
Total number of parts = 5 + 7 + 8 = 20
Parts with Dalila = 7/20
Money with Dalila =
= 7/20 of 68
= 7/20 × 68/1
= 476/20
= 23.8
Dalila has $23.8 with her .
Money she spends on a hat = $12
Money left with her =
= 23.8 - 12
= 11.8
Therefore , Dalila has $11.8 left with her , after she buys a hat .
Solution to the problems in the comment box :-
Solution (1) :
Ratio of cement to sand to aggregate to water = 2:5:8:1
Total parts = 2 + 5 + 8 + 1 = 16 parts
Number of parts for aggregate = 8/16
Then the aggregate needed by Bobbie =
= 8/16 × 1.2
= 1/2 × 1.2
= 1.2 as a fraction will be 6/5
= 1/2 × 6/5
= 6/10
6/10 as a decimal = 0.6
Therefore , Bobbie needs 0.6 cube of meter .
Solution (a) :
Cement : sand : aggregate : water = 2:5:8:1
Total parts = 16
Number of parts for cement = 5/16
Let the quantity of concrete be = x
Then ,
Cement =
= 5/16 of x
= 5/16x = 0.25 meter cube
= x = 0.25 × 16/5
= x = 25/100 × 16/5
= x = 1/4 × 16/5
= x = 16/20
= x = 4/5
4/5 as decimal = 80/100 = 0.08
Cement needed by Eddie = 0.08 cubic meter .
Quantity of water Eddie will need =
= 1/16 × 0.08
= 1/16 × 80/100
= 1/16 × 8/10
= 8/60
= 0.13
Water needed by Eddie = 0.13 cubic meter .
Quantity of aggregate needed by Eddie =
= 8/16 × 80/100
= 1/2 × 8/10
= 8/20
= 40/100
= 0.04
Aggregate needed by Eddie = 0.04 cubic meter .
Quantity of sand Eddie will need =
= 5/16 × 80/100
= 5/16 × 8/10
= 40/160
= 0.25
Quantity of sand needed by Eddie = 0.25 cubic meter .
Therefore , Eddie will need 0.25 cubic meter of sand , 0.04 cubic meter of aggregate ,0.13 cubic meter of water along with 0.25 cubic meter of cement to make concrete .
Solution (b) :
When water and aggregate has been added the quantity of concrete =
= 0.13 + 0.04
= 0.07
Therefore , when water and aggregate has been added the quantity of concrete will be 0.07 cubic meter .