Question

Plssssss help number 18 and 20​

Answer 1

Answer:

18).

Total mass of materials = 4.8kg

For gravel

55% of the materials are gravel

So we have

55/100 × 4.8 kg

= 2.64kg

For sand

30% of the materials are sand

We have

30/100 × 4.8

= 1.44kg

For cement

The remaining materials were cement so we add the masses of both the sand and gravel and subtract it from the total mass

That's

4.8 - (2.64 + 1.44)

4.8 - 4.08

= 0.72 kg

20).

She earns £ 800 per week

She receives a raise of 7.5% which is

100 + 7.5 = 107.5%

So we have

107.5 / 100 × £ 800

= £ 860

She now earns £ 860 per week

Hope this helps you

Answer 2

Step-by-step explanation:

1)of 4.8kg concrete 55% is gravel,30% is sand and 15% is cement.

percent=Rate*Base

Pgravel=55%*4.8kg

Pgravel=2.64kg

Psand=30%*4.8kg

Psand=1.44kg

Pcement=15%*4.8kg

Pcement=0.72kg

2)percent=Rate*Base

percent=7.5%*£800

percent=60£

total earn=60£ + £800

total earn=£860